Joint Start Topical by NutriStart Vitamin Company

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Wound healing. Preliminary clinical research shows that using adhesive dressing strips (Band-Aid) as a skin sealing dressing on percutaneous intervention access sites is preferable to sterile cotton soaked in compound benzoin tincture. Subjective scores for ease of application, comfort, and avoidance of postoperative wound complications are higher, and rates of contact dermatitis and wound infection are lower, with adhesive strips when compared with compound benzoin tincture (103827). More evidence is needed to rate benzoin for this use.

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INSUFFICIENT RELIABLE EVIDENCE to RATE

• Allergic rhinitis (hay fever). Although there has been interest in using oral black pepper for allergic rhinitis, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Asthma. Although there has been interest in using oral black pepper for asthma, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Athletic performance. Oral black pepper has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical trial in untrained males shows that taking a supplement containing black pepper extract 10 mg, caffeine 400 mg, capsicum extract 66.7 mg, and niacin 40 mg as a single dose prior to exercise does not improve strength, time to exhaustion, or maximal oxygen consumption when compared with placebo (37873).
• Depression. Although there has been interest in using oral black pepper for depression, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Diarrhea. Although there has been interest in using oral black pepper for diarrhea, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Dysmenorrhea. Although there has been interest in using oral black pepper for dysmenorrhea, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Dyspepsia. Although there has been interest in using oral black pepper for dyspepsia, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Fall prevention. It is unclear if inhaling black pepper oil as aromatherapy is beneficial for fall prevention in older adults. Details: One small clinical study in older adults shows that applying black pepper oil near the right side of the nose as an olfactory stimulant improves stability while the eyes are closed during a one-minute trial when compared with the application of water. The improvement with black pepper oil is comparable to the improvement seen with the application of lavender oil (29160). It is unclear if any benefit persists after inhalation of black pepper oil.
• Fatigue. It is unclear if oral black pepper is beneficial in patients with fatigue. Details: One small clinical trial in adults with below-average energy levels shows that taking black pepper 2 grams as a single dose does not improve sustained attention, motivation to perform cognitive tasks, or feelings of mental energy and mental fatigue when compared with placebo (91731).
• Flatulence. Although there has been interest in using oral black pepper for flatulence, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Headache. Although there has been interest in using oral black pepper for headache, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Insect bite. Topical black pepper has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical trial shows that applying a specific product (Trikatu) containing black pepper, long pepper, and ginger, as well as camphor, eucalyptus oil, and menthol, directly to mosquito bites does not reduce papule size, erythema, edema, or pruritis when compared with a control compound containing the same base ingredients but without the pepper and ginger components (89893).
• Obesity. Although there has been interest in using oral black pepper for obesity, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Pain (chronic). Although there has been interest in using topical black pepper for chronic pain related to various etiologies, including osteoarthritis, postherpetic neuralgia, and peripheral neuropathy, there is insufficient reliable information about the clinical effects of black pepper for these conditions.
• Rhinosinusitis. Although there has been interest in using oral black pepper for rhinosinusitis, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Sexual desire. Although there has been interest in using oral black pepper for increasing sexual desire, there is insufficient reliable information about the clinical effects of black pepper for this purpose.
• Smoking cessation. It is unclear if inhaling black pepper essential oil as aromatherapy is effective for smoking cessation. Details: One small clinical trial in adult male smokers who were deprived from smoking overnight shows that inhaling a vapor from the essential oil of black pepper, as needed over a 3-hour period, reduces cigarette cravings, negative feelings, and anxiety when compared with a placebo vapor (29159). Another small clinical study in patients addicted to dipping, chewing, or smoking tobacco shows that placing a drop of black pepper essential oil on tissue paper and inhaling for 2 minutes at least three times a day for 3 days reduces nicotine cravings when compared to baseline (90502).
• Swallowing dysfunction. It is unclear if inhaling black pepper oil as aromatherapy is beneficial in patients with swallowing dysfunction. Details: One small clinical study in post-stroke residents of nursing homes shows that one minute of olfactory stimulation with black pepper oil before each meal for 30 days decreases swallowing reflex latency by 11 seconds and increases the number of swallowing movements by 3.3 when compared to baseline (29161). A small clinical trial in children with neurological disorders who were on long-term enteral nutrition shows that applying black pepper oil to the nostrils or nasal cavity for one minute improves the amount of oral intake and swallowing movement in 63% of patients. Although oral intake increased, the need for enteral nutrition was not eliminated (29162).
• Vitiligo. It is unclear if topical piperine oil, a constituent of black pepper, is beneficial in patients with vitiligo. Details: A small clinical study in patients with vitiligo shows that applying piperine oil 1% daily in addition to receiving narrowband ultraviolet B (NB-UVB) light therapy every other day for 3 months improves repigmentation more rapidly when compared with using NB-UVB alone (103820). More evidence is needed to rate black pepper for these uses.

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There is insufficient reliable information available about the effectiveness of bois de rose oil.

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POSSIBLY EFFECTIVE

• Dysmenorrhea. In people with dysmenorrhea, taking oral ginger seems to reduce pain. Clinical research shows that ginger might be comparable to ibuprofen or mefenamic acid. In addition, taking ginger seems to be beneficial when used as an adjunct to mefenamic acid 250 mg twice daily. Details: Clinical research in individuals at least 15 years of age shows that ginger can reduce pain from dysmenorrhea. Clinical studies show that taking ginger powder 500-2000 mg daily usually for the first 3-4 days of a menstrual cycle modestly decreases pain severity by an average of 2.3-2.7 points on a 10-point scale when compared to control groups (89889,89899,91139,91892,96255,106077). However, a meta-analysis of clinical research shows that taking ginger does not reduce pain duration when compared with placebo (106077). Clinical research also shows that ginger might be as effective as some anti-inflammatory agents. Taking a specific ginger extract (Zintoma, Goldaru) 250 mg four times daily for 3 days at the beginning of the menstrual period or until pain relief improves symptoms similarly to ibuprofen or mefenamic acid (17931,96259,106077). Also, taking a ginger extract 200 mg four times daily for 3-4 days at the beginning of pain is equally effective to taking Novafen, a combination of acetaminophen, caffeine, and ibuprofen (99444). Ginger also seems to improve pain when given as an adjunct to anti-inflammatory agents. A small clinical study in young females with dysmenorrhea shows that adding ginger (Vomigone, Dineh Co.) 500 mg daily to mefenamic acid 250 mg twice daily for 5 days further reduces pain when compared with taking mefenamic acid alone (102464).
• Osteoarthritis. Most clinical research shows that taking ginger extract by mouth improves pain in some patients with osteoarthritis. Topical ginger, on the other hand, has not shown benefit for knee osteoarthritis in low quality research. Details: Meta-analyses of clinical research show that taking ginger extract 500-1000 mg daily for 3-12 weeks can modestly improve pain when compared with placebo in some patients with osteoarthritis of the knee or hip (96253,103357). However, a meta-analysis of two clinical studies shows that taking ginger extract about 500 mg daily for 6 weeks does not have an effect on function (103357). One small clinical trial in patients with mild osteoarthritis of the knee also shows that taking steamed golden ginger extract 480 mg daily for 12 weeks moderately improves pain and functional scores when compared with placebo (114784). Some clinical research has also compared ginger to conventional drug treatment. In one clinical trial, there was no significant difference between ginger extract 30 mg daily and ibuprofen 400 mg three times daily for one month in patients with osteoarthritis of the hip or knee (17930). However, taking a specific ginger extract (Eurovita Extract 33; EV ext-33) orally 170 mg three times daily for 3 weeks was significantly less effective than ibuprofen 400 mg three times daily for reducing pain (7048). Since ginger is thought to take several weeks for significant benefit, this trial might not have lasted long enough. Ginger has also been compared with diclofenac. When used orally as 1500 mg daily in two divided doses, ginger is less effective than oral diclofenac 100 mg daily in two divided doses, or the combination of ginger and diclofenac, for 12 weeks (89898). Various studies have evaluated formulations containing ginger with other ingredients. These combinations have all been shown to improve osteoarthritis pain, and in some cases, functionality. Studied formulations include ginger (Eurovita Extract 35; EV ext-35) 340 mg with glucosamine (Zinaxin glucosamine, Ferrosan AS) 1000 mg daily for 4 weeks, a ginger extract with an alpinia (Alpinia galanga) extract (Eurovita Extract 77; EV ext-77) 255 mg twice daily for 6 weeks, a ginger extract with curcuminoids, and extracts of devil's claw, Boswellia serrata, and celery (Tregocel) for 36 weeks, or Ayurvedic shunthi-guduchi formulations containing ginger, Indian gooseberry, and Tinospora cordifolia, either with or without Boswellia serrata (7084,18210,89557,106078). However, it's too early to know if the effects of these combination agents are associated with ginger or other ingredients in the formulations. Topical ginger, alone or in combination with other ingredients, has also been studied for knee osteoarthritis. Although a meta-analysis of two randomized clinical trials shows no evidence of benefit of topical ginger for pain and disability when compared with placebo or standard therapy (103357), some benefits have been shown in individual preliminary studies (20340,20341,89897,96668,97537,97542). These trials have used a specific gel containing ginger and plai 4% by weight (Plygersic gel, Thailand Institute of Scientific and Technological Research) 4 grams/day in four divided doses for 6 weeks (89897), an ointment composed of ginger, cinnamon, mastic (Saghez), and sesame oil twice daily for 6 weeks (20340), or one gram of ginger extract 5% (standardized to 11.18% of 6-gingerol) in a nanostructure lipid carrier three times daily for up to 12 weeks to the affected knee (96668,97537). Some studies have used ginger essential oil in a massage oil, alone or with sweet orange essential oil or standard therapy, twice weekly for 3 or 6 weeks (20341,97542).
• Pregnancy-induced nausea and vomiting. Oral ginger seems to reduce the severity of nausea and vomiting in some people during pregnancy. Ginger seems to be more effective than placebo, comparable to vitamin B6 or dimenhydrinate, and less effective than metoclopramide. Details: Although most clinical studies are small and have methodological limitations, the available research shows that ginger is more effective than placebo, and comparable to vitamin B6 or dimenhydrinate (721,1922,5343,11346,13071,16306,20312,20315,90103,91201,102462). Although ginger is comparable to dimenhydrinate for reducing symptoms of morning sickness, it seems to take about 3 days to reduce vomiting episodes compared to 1 day with dimenhydrinate (16305). In addition, clinical research shows that ginger is less effective than metoclopramide at relieving nausea and vomiting associated with pregnancy (20315). Ginger doses of 500 to 2500 mg daily, divided into two to four daily doses for 3 days to 3 weeks, have been used in clinical research (721,5343,16305,16306,20312,20315,90103,91201). The American College of Obstetrics and Gynecology (ACOG) considers ginger capsules 250 mg 4 times daily a first-line nonpharmacological treatment option for pregnancy-induced nausea based on limited evidence. However, there is no evidence that ginger reduces vomiting (111601).

POSSIBLY INEFFECTIVE

• Chemotherapy-induced nausea and vomiting (CINV). Most clinical research shows that oral ginger does not reduce acute or delayed CINV. The effect of ginger might depend on the dose, the other antiemetics used, or the specific chemotherapy regimen. Details: Most clinical research shows that taking ginger as adjunct to adequate antiemetic therapy does not reduce DELAYED CINV when compared with antiemetic therapy alone (20316,96260,89891,96675,97538,97541,101760,102461,113616). Clinical research from meta-analyses and most individual clinical studies also show that taking ginger 0.5-3.5 grams as an adjunct to standard antiemetic therapy does not reduce the incidence or severity of ACUTE CINV when compared with antiemetic therapy alone (89891,96675,101760,102461,102466,113616). However, conflicting results exist from some individual clinical studies (20316,102466). These individual studies evaluated powdered ginger root or liquid extract of ginger root 0.5-2 grams taken in two to four divided doses daily, starting on either the day of or 3 days before chemotherapy and continuing for 3-5 days after chemotherapy initiation (20316,102466). Also, one small study shows that ginger in doses of 1 gram or less for more than 3 days reduces the likelihood of acute vomiting by 60% (101760). More research is needed to confirm the efficacy of this lower dose. Reasons for the conflicting results are unclear, but several theories have been postulated. One theory is that ginger might help reduce CINV associated with some, but not all, chemotherapy regimens. One preliminary clinical study shows that ginger 500 mg twice daily for 3 days reduces vomiting in patients receiving cyclophosphamide and doxorubicin, but not in patients also receiving 5-fluorouracil or docetaxel (96251). However, since there is limited evidence supporting this theory, additional research is needed to confirm. Another theory is that ginger helps when used with certain antiemetic drugs, but not others. For example, ginger seems to help in cases when optimal antiemetic therapy, such as 5-HT3 receptor antagonists, is not available. Small clinical studies show that ginger reduces the severity of acute nausea when compared with prochlorperazine or metoclopramide, both of which are suboptimal antiemetic therapy for CINV (89891). Another small study shows that ginger is comparable to metoclopramide for improving delayed chemotherapy-induced nausea (13244). On the other hand, several studies show that taking ginger 0.5-2 grams daily along with antiemetic therapy that includes aprepitant does NOT improve acute or delayed CINV (20318,89891,96251,96675). In fact, one study found an association between concomitant use of ginger 2 grams daily with aprepitant and worsened severity of delayed nausea. Ginger is hypothesized to decrease the absorption of aprepitant and reduce its effectiveness for delayed nausea (20318,96675). However, this effect has not been replicated, and aprepitant serum levels were not measured to confirm this hypothesis. Finally, many of the studies showing a benefit of ginger for CINV when used as an adjunct to standard antiemetic therapy are considered to be methodologically flawed (20317,96252,96677). For instance, one study using powdered ginger root 1-2 grams daily during the first three days of chemotherapy in children and adults (20317) has been criticized for inaccurately representing data (89891). Other studies of ginger 500 mg twice daily for up to 10 days used questionable methods to measure outcomes and usually did not differentiate between acute and delayed CINV (96252,96677). Ginger essential oil aromatherapy has also been evaluated. One small study shows that using two drops of ginger essential oil on an aromatherapy necklace for 2 minutes daily for 5 days, starting on the first day of chemotherapy, reduces acute nausea, but not vomiting or delayed nausea, when compared with placebo in females with breast cancer taking standard antiemetics including granisetron, dexamethasone, and metoclopramide (96256).
• Exercise-induced muscle soreness. Most research shows that oral ginger in single or multiple doses does not prevent or treat exercise-induced muscle soreness. Details: Two small studies in healthy adults show that single doses of ginger supplements do not seem to reduce muscle soreness from exercise. Taking capsules of ground ginger 2 grams, 30 minutes before a 30-minute cycling bout, or 24-48 hours after eccentric exercise, does not reduce muscle pain during exercise or within one hour of ingestion when compared with placebo (17932,17934). Taking multiple doses also does not seem to help. One small study in healthy adults shows that taking capsules with ginger powder 4 grams daily for 5 days before high-intensity eccentric exercise does not reduce muscle soreness over 4 days when compared with placebo (96258). Another small study in healthy adults shows that taking capsules of heated or raw ground ginger 2 grams daily for 8 days prior to eccentric exercise, and continuing supplementation for 3 more days, might modestly reduce muscle soreness 24 hours post-exercise, but not at later time points, when compared with placebo (17933,96258). Ginger has also been tested in combination with other ingredients. One small study in healthy adults shows that taking a specific combination product (ReWin(d), Natural Origins) containing a 4:3 ratio of ginger and annatto powder, 2 grams in divided doses daily for 4 weeks before eccentric exercise and continuing for 3 days after exercise, may modestly reduce muscle pain 48 hours after exercise but not at other time points (105057). This study was funded by the supplement manufacturer.
• Motion sickness. Most research shows that oral ginger does not prevent or treat motion sickness. Details: Most clinical research shows that taking ginger 500-1000 mg up to 4 hours prior to travel does not prevent motion sickness (7624,7625,20330,20331). Some patients report subjective feelings of improvement, but in many studies objective measures did not significantly improve (7400). However, one clinical trial suggests that ginger is more effective than dimenhydrinate at reducing gastrointestinal distress associated with motion sickness (20332). Another clinical study seems to show that taking ginger 1-2 grams as a single dose reduces nausea severity and increases the latency before the onset of nausea caused by simulated motion sickness when compared to baseline (20333). The validity of this finding is limited by the lack of a comparator group.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acute respiratory distress syndrome (ARDS). Some small clinical studies show that giving ginger with tube feeds to hospitalized patients might reduce the duration of serious sequelae from ARDS. Details: A small clinical trial in adults with ARDS shows that administering ginger extract 120 mg in three divided doses daily via nasogastric tubing for 21 days increases the number of ventilator-free days and the amount of feeding tolerated and decreases the number of intensive care unit (ICU) days when compared with placebo. However, it does not seem to improve overall mortality (20343). Also, another small clinical study shows that adding ginger extract 120 mg to tube feeds in three divided doses daily for 8-21 days improves blood oxygen levels by 13% to 20%, as well as the ability of the lungs to expand by 17%, when compared with a coconut oil placebo. The duration of mechanical ventilation and stay in the ICU also improved. However, ginger does not affect other measurements of lung function or physical organ damage in these patients (89886).
• Allergic rhinitis (hay fever). It is unclear if oral ginger is beneficial in allergic rhinitis. Details: A small clinical trial shows that taking ginger extract 500 mg daily for 6 weeks is as effective as loratadine 10 mg daily for reducing nasal symptoms of allergic rhinitis (103359).
• Antiretroviral-induced nausea and vomiting. Oral ginger seems to improve nausea and vomiting in patients using antiretroviral agents. Details: A small clinical study in patients with HIV shows that taking ginger 0.5 grams twice daily, 30 minutes prior to each dose of antiretroviral for 14 days, reduces the relative likelihood of nausea and vomiting by about 63% and 79%, respectively, when compared with placebo (89887).
• Asthma. Although there has been interest in using oral ginger for asthma, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Atopic dermatitis (eczema). Topical ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A moderate-sized clinical trial in adults and children with eczema shows that applying a combination topical product containing ginger and cannabidiol twice daily for 5 days moderately improves eczema scores, including erythema, dryness, itching, and scaling, when compared to baseline. It is unclear if this effect is due to ginger, other ingredients, or the combination. The validity of this study is limited by the lack of a comparator group (114783).
• Back pain. Although there has been interest in using oral ginger for back pain, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Burns. Although there has been interest in using topical ginger for burns, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Cancer-related anorexia. It is unclear if oral ginger improves appetite in people with cancer-related anorexia. Details: A small clinical study in patients with cancer-related anorexia and cachexia shows that taking a capsule containing ginger 1650 mg daily for 14 days improves nausea, appetite, reflux, dysmotility, and other gastrointestinal symptoms when compared to baseline (102460). The validity of these findings is limited by the lack of comparator group.
• Chronic obstructive pulmonary disease (COPD). Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking two capsules of a specific combination product (AKL1, AKL International Ltd.) containing ginkgo extract, ginger, and Picrorhiza kurroa twice daily for 8 weeks does not improve respiratory symptoms when compared with placebo in patients with COPD (89702). Another moderate-sized clinical study in adults with COPD shows that taking a combination product containing extracts of ginger, alpinia, cardamom, cinnamon, and saffron in honey 3 times daily for 8 weeks improves confidence in leaving home and the ratio of forced exploratory volume per second to forced vital capacity of the lungs (FEV1/FVC) when compared with placebo. However, the combination product does not improve most measures of respiratory function or symptoms such as cough, phlegm, chest tightness, dyspnea, reduced energy levels, sleeping disorders, or activity limitations when compared with placebo (111542). It is unclear if these effects are due to ginger, other ingredients, or the combination.
• Colic. Although there has been interest in using oral ginger for colic, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Constipation. Although there has been interest in using oral ginger for constipation, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Coronavirus disease 2019 (COVID-19). It is unclear whether oral ginger is beneficial for patients with COVID-19. Details: Clinical research in adults hospitalized with asymptomatic COVID-19 infection shows that taking ginger 1.5 grams twice daily orally until hospital discharge reduces length of stay from around 8.5 days to 6 days, when compared with placebo. The strongest effect is seen in males over 60 years of age (110005). The relevance of these results is reduced by a lack of blinding, and the fact that the subjects were initially asymptomatic. Another small study in adults with COVID-19 treated in the community shows that taking ginger 1000 mg three times a day for 7 days does not improve viral clearance, oxygen saturation, or respiratory rate when compared with placebo. Taking ginger also did not reduce the risk of hospitalization (114779). The efficacy of ginger for treating COVID-19 has also been evaluated in combination with other ingredients. In adults with uncomplicated, moderate COVID-19, taking a combination of ginger, turmeric, ashwagandha, and boswellia (BV-4051, Artovid-20), 1776 mg twice daily orally for 14 days in addition to standard care and starting 48-96 hours after symptom onset, reduces the mean duration of symptoms from about 8 days to 7 days, when compared with placebo (109899). A small open-label study in adults with confirmed mild to moderate COVID-19 shows that taking ginger 1000 mg and ashwagandha 500 mg twice daily for 15 days, along with conventional therapy, leads to a 13.8-fold and 2.6-fold increase in the relative rate of clinical cure at 7 days and 15 days, respectively, when compared with conventional therapy alone. Taking this combination also appears to reduce time to recovery by around 6 days but does not improve the rate of negative COVID-19 tests, chest imaging findings, viral clearance, serum antibodies, or other measures of disease progression when compared with conventional therapy alone (112094). The validity of these findings is limited by a lack of blinding, and the study may have been inadequately powered to detect a difference between groups. Additionally, it is unclear if these effects are due to ginger, ashwagandha, or the combination.
• Diabetes. Some preliminary clinical studies suggest that oral ginger might have a small beneficial effect on glycemic control in patients with type 2 diabetes or gestational diabetes. Details: Meta-analyses of several small clinical trials in adults with type 2 diabetes show that taking ginger 1200-3000 mg daily for 8-13 weeks reduces glycated hemoglobin (HbA1c) by around 0.6% to 1% and fasting blood glucose by 19-21 mg/dL when compared with placebo (96680,107898). However, a recent meta-analysis of randomized clinical trials in adults with type 2 diabetes shows that taking ginger 1200-2000 mg daily for 4-12 weeks does not improve HbA1c or fasting blood glucose when compared with placebo (114780). The reasons for these discordant results are not entirely clear, but they are likely related to heterogeneity of the included populations, treatment dose, and duration of follow up. Additionally, a small clinical study in adults with diabetes on hemodialysis for end stage renal disease shows that taking ginger powder 2000 mg daily for 8 weeks reduces fasting blood glucose and measures of insulin resistance, but not serum insulin levels, when compared with placebo (111543). In patients with gestational diabetes at weeks 24-28 of pregnancy, clinical research shows that taking ginger 1500 mg daily in three divided doses for 6 weeks reduces fasting blood glucose, insulin levels, and measures of insulin resistance by a small amount when compared with placebo, with no effect on postprandial glucose levels (103358).
• Diabetic neuropathy. Topical ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial in adults treated with gabapentin for diabetic neuropathy of the foot shows that applying a combination balm containing ginger, menthol, camphor, and other ingredients three times a day for 4 weeks moderately improves pain scores when compared with a placebo balm without ginger but containing menthol, camphor, and other ingredients.(114781). It is unclear if this effect is due to ginger, other ingredients, or the combination.
• Diarrhea. Although there has been interest in using oral ginger for various types of diarrhea, including cholera and acute bacterial dysentery, there is insufficient reliable information about the clinical effects of ginger for these conditions.
• Dry mouth. It is unclear if rinsing the mouth with ginger extract is beneficial for dry mouth. Details: In patients with dry mouth related to type 2 diabetes, clinical research shows that use of a ginger extract 25% mouthwash 20 mL three times daily for 14 days modestly reduces symptoms of dry mouth when compared with rinsing with a saline control mouthwash (106068). Although this study was indicated as being triple-blind, it is unclear how the taste of ginger was masked.
• Dyspepsia. It is unclear if oral ginger is beneficial for dyspepsia. Details: In patients with dyspepsia, a small clinical trial shows that a single dose of ginger root powder 1.2 grams, taken 1 hour prior to eating, does not reduce abdominal discomfort when compared with placebo. However, it increases the rate of gastric emptying (20325).
• Erectile dysfunction (ED). It is unclear if oral ginger is beneficial for erectile dysfunction. Details: Preliminary clinical research in middle-aged males with ED shows that taking two capsules of a specific combination product (Revactin, MD Concepts LLC) containing ginger root 250 mg, muira puama 250 mg, guarana 250 mg, and L-citrulline 800 mg twice daily for 3 months improves scores related to erectile function and intercourse satisfaction, but does not improve sexual desire or orgasmic function scores, when compared to baseline (103224). This study is limited by the lack of a placebo control, the use of per-protocol analysis, and a high dropout rate. In fact, 44% of patients withdrew in order to resume use of phosphodiesterase type 5 (PDE5) inhibitors. Further, it is unclear if these effects are due to ginger, other ingredients, or the combination.
• Gastroenteritis-associated nausea and vomiting. It is unclear if oral ginger is beneficial for children with gastroenteritis-associated vomiting. Details: In children aged 1-10 years with acute gastroenteritis-associated vomiting, clinical research shows that taking a single dose of ginger reduces the risk of vomiting at least once in the subsequent 8 hours by 20% when compared with placebo. The incidence of vomiting over the next 24 and 48 hours was also modestly reduced. The children were given 20 drops of ginger equivalent to 10 mg immediately, followed by every 8 hours until cessation of vomiting. All children were offered hypotonic oral rehydration solution (ORS) 30 minutes after the first dose (106076). The number of children accepting ORS, and the quantity of ORS consumed, was less in the group receiving placebo. It is unclear if this affected the outcomes of this study. Also, the incidence or severity of nausea was not investigated.
• Hangover. It is unclear if oral ginger is beneficial for managing symptoms of hangover. Details: Preliminary clinical research shows that use of a decoction containing a combination of ginger 6 grams, pith of Citrus tangerine 3 grams, and brown sugar decreases symptoms of alcohol hangovers, including nausea, vomiting, and diarrhea, when compared with placebo. The decoction was taken once 5 hours prior to drinking alcohol or four times after drinking alcohol (20320).
• Hyperlipidemia. Oral ginger may be modestly beneficial for some patients with hyperlipidemia. Details: A meta-analysis of preliminary clinical research in adults with and without hyperlipidemia shows that taking ginger 200-3000 mg orally daily for 2-24 weeks reduces triglyceride and low-density lipoprotein cholesterol levels by 12 mg/dL and 5 mg/dL, respectively, and increases high-density lipoprotein cholesterol levels by 1 mg/dL when compared with placebo (109521). However, the validity of this study is limited by high heterogeneity. A clinical study in adults with hyperlipidemia shows that taking ginger powder 1 gram three times daily for 45 days reduces triglyceride and cholesterol levels by an additional 36% and 90%, respectively, when compared with placebo (20327).
• Hypertension. It is unclear if oral ginger is beneficial for lowering blood pressure. Details: A preliminary clinical study in patients with diabetes and elevated systolic blood pressure shows that drinking black tea containing ginger 3 grams three times daily for 8 weeks does not reduce blood pressure by a clinically significant amount when compared with plain black tea (96669).
• Hypothyroidism. It is unclear if oral ginger is beneficial in patients with hypothyroidism. Details: A small clinical study in patients with primary hypothyroidism who are stabilized on thyroid hormone therapy shows that taking ginger powder 500 mg twice daily for 30 days improves symptoms associated with hypothyroidism, including cold intolerance, constipation, dizziness, dry skin, weight gain, and concentration and memory issues, when compared with placebo. However, ginger supplementation does not seem to improve hair loss, hearing, nail fragility, speech, or feelings of depression in these patients (107903).
• Insect bite. It is unclear if topical ginger is beneficial for reducing the size of insect bites. Details: Preliminary clinical research shows that a topical application of Trikatu, which contains ginger, long pepper, and black pepper extracts with 0.074% piperine and 0.046% gingerol, does not reduce the papule size associated with mosquito bites when compared with a control compound containing the same base ingredients of camphor 2%, menthol 2%, and eucalyptus oil 4% (89893).
• Intraoperative nausea and vomiting (IONV). It is unclear if oral ginger is beneficial for preventing IONV. Details: Clinical research in individuals undergoing elective C-section and receiving cimetidine and metoclopramide, shows that taking ginger 1 gram orally 30 minutes prior to anesthesia reduces the number of episodes of intraoperative nausea, but not vomiting, when compared with placebo (89890). In other clinical research in adults undergoing elective surgical procedures, adding ginger to a high calorie drink consumed pre-operatively reduces the incidence of nausea from 40% to 10%, and the incidence of vomiting from 25% to 10% when compared with the high calorie drink alone (110007). The validity of these results is unclear as only patients were blinded to the treatment group.
• Irritable bowel syndrome (IBS). Oral ginger might reduce symptoms of IBS when used in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial shows that taking ginger 1-2 grams daily for 28 days does not improve symptoms or the number of responders when compared with placebo (90102). However, some research shows that ginger might be beneficial in some patients when used along with other herbal ingredients. Taking a capsule containing ginger, boswellia, and yarrow three times daily for 30 days reduces the frequency and severity of abdominal pain, as well as the severity of bloating, when compared with placebo in females, but not males, with mild to moderate IBS (96673). Another clinical study shows that taking an herbal mixture containing ginger, English horsemint, and purple nut sedge tuber three times daily for 8 weeks improves IBS symptoms including abdominal pain, stool frequency, stool consistency, incomplete evacuation, and urgency, when compared to baseline; these improvements are similar to those achieved by taking mebeverine 135 mg three times daily (89900). However, it is unclear if these effects are due to ginger, other ingredients, or the combination.
• Joint pain. Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking a specific combination product (Instaflex Joint Support, Direct Digital) containing glucosamine sulfate 1500 mg, methylsufonlylmethane 500 mg, white willow bark extract 250 mg, ginger root concentrate 50 mg, Boswellia extract 125 mg, turmeric root extract 50 mg, cayenne 40 m H.U. 50 mg, and hyaluronic acid 4 mg in three divided doses daily for 8 weeks reduces joint pain severity by 37% compared to only 16% with placebo. However, it does not improve joint stiffness or function when compared with placebo (89560). It is unclear if these effects are due to ginger, other ingredients, or the combination.
• Menorrhagia. It is unclear if oral ginger is beneficial for menorrhagia. Details: Preliminary clinical research in healthy adults experiencing heavy menstrual bleeding shows that taking ginger 250 mg three times daily for 4 days, starting the day prior to menstruation, and repeating for three menstrual cycles, reduces the amount of menstrual bleeding when compared with placebo (96672).
• Menopausal symptoms. Although there has been interest in using oral ginger for menopausal symptoms such as insomnia, there is insufficient reliable information about the clinical effects of ginger for this purpose.
• Migraine headache. Small clinical studies suggest that oral ginger may modestly reduce migraine pain severity and duration. However, taking ginger doesn't seem to PREVENT migraines. Details: Ginger does not seem to be effective for the prevention of migraines. Clinical research in patients with episodic migraine shows that taking ginger extract 200 mg three times daily for 3 months does not reduce the number of migraine attacks, the use of analgesics, or the number of days with pain, any more than taking placebo (101761). However, ginger may be beneficial for the treatment of migraine. Clinical research shows that taking ginger extract 400 mg orally in the emergency room along with intravenous ketoprofen 100 mg reduces pain over the next 2 hours when compared with ketoprofen and placebo. This combination also resulted in an overall better response with a higher likelihood of having no or mild pain with treatment (101762). Taking ginger 250 mg at the onset of a common migraine headache seems to be as effective as taking sumatriptan 50 mg for reducing headache severity within two hours of treatment (89894). Furthermore, a combination of ginger and feverfew (GelStat Migraine, GelStat Corporation; LipiGesic M, PuraMed BioScience), administered sublingually at the onset of a migraine attack, decreases the duration and intensity of migraine pain when compared with placebo (19357,22602). It is unclear if these effects are due to ginger, feverfew, or the combination. Feverfew alone has demonstrated some benefit in treating migraines.
• Multiple sclerosis (MS). It is unclear if oral ginger is beneficial for MS. Details: A small clinical study in adults with MS shows that taking ginger 500 mg three times daily for 12 weeks reduces disability scores and improves physical and psychological quality of life scores when compared with placebo (111541). Another small clinical study in adults with relapsing-remitting MS shows that taking ginger 500 mg three times daily for 12 weeks reduces the frequency and severity of nausea and constipation and the severity but not frequency of bloating when compared with placebo. However, no improvement was noted in other gastrointestinal symptoms of MS including abdominal pain, anorexia, diarrhea, dysphagia, gas, or heartburn (113614).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral ginger is beneficial for NAFLD. Details: A small clinical study in patients with NAFLD shows that taking ginger 1000 mg twice daily for 12 weeks improves liver steatosis scores but not liver fibrosis scores when compared with placebo. Ginger also modestly improves levels of alanine aminotransferase and gamma-glutamyl transferase but not aspartate aminotransferase (113615). However, it is unclear whether any improvements are clinically significant. Another small clinical study in patients with NAFLD shows that taking ginger root 1500 mg daily for 12 weeks reduces low-density lipoprotein (LDL) cholesterol and fasting blood glucose levels, but does not affect triglycerides, high-density lipoprotein (HDL) cholesterol, insulin resistance, blood pressure, or fatty liver index, when compared with placebo (102465).
• Obesity. Oral ginger has primarily been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Although some individual research disagrees (40802), a meta-analysis and most individual clinical trials show that taking ginger alone or with other ingredients does not reduce weight by a clinically significant amount when compared with placebo in overweight or obese individuals (20346,20347,96676,109521). Ginger has been taken alone or in combination with green tea and capsaicin; rhubarb, astragalus, red sage, turmeric, and gallic acid (Number Ten); or raspberry ketone (Razberi K, Integrity Nutraceuticals), caffeine, capsicum extract (Capsimax, OmniActive Health Technologies), bitter orange fruit (Advantra Z, Nutratech Inc), L-theanine, and black pepper fruit extract (Biperine, Sabinsa Corporation) (Prograde Metabolism) (20346,20347,40802,96676). Due to the various other ingredients contained in available formulations, any effect from ginger is unclear.
• Parturition. It is unclear if bathing in a ginger bath is beneficial for shortening the duration of labor. Details: Preliminary clinical research shows that bathing in 228 liters of water containing 4 drops of ginger essential oil does not shorten the duration of labor when compared with a regular bath (20345).
• Polycystic ovary syndrome (PCOS). It is unclear if oral ginger is beneficial for females with PCOS. Details: Preliminary clinical research in females with PCOS shows that taking ginger 500 mg three times daily orally for 8 weeks decreases body weight, body mass index, and levels of follicle stimulating hormone and luteinizing hormone, when compared with placebo. It does not affect testosterone levels (110006).
• Postoperative nausea and vomiting (PONV). Evidence for the use of oral ginger for preventing PONV is inconclusive and conflicting. Reasons for the conflicting findings may relate to the ginger formulation used and the outcomes measured. It is unclear if ginger aromatherapy is beneficial for PONV. Details: Some individual clinical studies, as well as a large, recent meta-analysis of the available clinical research, show that taking ginger by mouth 1 hour prior to surgery does not reduce the incidence of 24-hour PONV (3452,3453,17369,99445). Also, the meta-analysis found that, although ginger reduces the severity of PONV when measured on a visual analogue scale (VAS), it does not reduce the severity of PONV when measured on a verbal descriptive scale (VDS). Furthermore, ginger does not reduce the use of rescue antiemetic medications (99445). However, some small, individual clinical studies and a meta-analysis of older clinical research show that taking ginger by mouth prior to surgery reduces the incidence of 24-hour PONV by up to 16% to 38% (722,723,1919,13237,20336,20338,20339). In addition, large clinical trials show that the frequency and severity of PONV 2-6 hours after surgery are similar when ginger 1 gram is given orally or when medications such as metoclopramide or dexmedetomidine are given intravenously prior to undergoing anesthesia (103356,103360). However, taking ginger prior to general anesthesia, in combination with other antiemetics like dexamethasone or cimetidine and metoclopramide, does not seem to reduce nausea and vomiting when compared with the other medications alone (20337,89890). In contrast, other research shows that powdered ginger 1-2 grams 30-60 minutes before induction of anesthesia has been used in most studies showing benefit, occasionally followed by 1 gram of ginger administered two hours after surgery (722,723,13237,20336,20338,103356,103360). Ginger aromatherapy has also been evaluated for the prevention of PONV. Application of 5% ginger essential oil to the wrists of patients prior to the induction of general anesthesia seems to prevent PONV in approximately 80% of treated patients (20334). Also, use of ginger essential oil aromatherapy on a gauze pad results in nausea relief in approximately 67% of patients compared with 40% in the placebo group; however, a blend of essential oils including ginger, spearmint, peppermint, and cardamom, results in nausea relief in 82% of patients (89888).These conflicting findings may be due to differences in outcome measures and the chemical compositions of ginger preparations used in the various clinical studies. Some evidence suggests that the efficacy of ginger for preventing PONV differs based on the formulation used. A network meta-analysis of 18 studies evaluating various ginger preparations, including ginger oil, ginger powder, ginger extract, and a combination of ginger powder and antiemetics, for the prevention of PONV suggests that ginger powder and ginger oil are the most effective formulations for preventing nausea and vomiting, respectively. The analysis also shows that while no ginger formulation is superior to another for the prevention of nausea, ginger powder and ginger oil have a lower risk of postoperative vomiting when compared with ginger extract. A subgroup analysis suggests that ginger seems to be most effective in adults over 30 years of age, when administered preoperatively, and when used for gastrointestinal, hepatobiliary, obstetric, or ophthalmic surgeries (112108).
• Postoperative recovery. It is unclear if oral ginger is beneficial for postoperative recovery. Details: One preliminary clinical study in adults who had a tonsillectomy shows that taking a specific ginger supplement (Solgar, Leonia) 500 mg twice daily for 7 days along with acetaminophen and antibiotics modestly improves pain and wound healing when compared with acetaminophen and antibiotics alone (96674).
• Postpartum complications. It is unclear if oral ginger is beneficial in patients with postpartum pain. Details: A small clinical study in patients recovering from vaginal delivery shows that taking ginger powder 500 mg 8-hours post-delivery, followed by 250 mg every 8 hours thereafter for 24 hours, reduces postpartum pain by nearly 1 point on a 10-point rating scale when compared with placebo (107904). It is unclear if this improvement would be considered clinically relevant.
• Radiation-induced nausea and vomiting. It is unclear if oral ginger is beneficial in patients with radiation-induced nausea and vomiting. Details: A very small study in adults with cervical cancer undergoing treatment with cisplatin and radiotherapy shows that taking ginger 250-500 mg twice daily for 6 weeks in addition to standard antiemetic therapy does not reduce acute or delayed nausea and vomiting when compared with antiemetic therapy alone (113616).
• Rheumatoid arthritis (RA). One small clinical study suggests that oral ginger may improve some symptoms of RA. Details: Preliminary clinical research in adults with RA shows that taking ginger powder 1500 mg daily for 12 weeks improves disease activity on the Disease Activity Score-28 when compared with placebo (100697). Another small study in adults with RA shows that taking a combination product containing ginger, ashwagandha, black pepper, and colchicum luteum twice daily for 4 weeks does not improve RA disease scores when compared with celecoxib 100 mg orally twice daily (114785). However, the interpretation of these results is limited by. poor methodology, and the study may have been inadequately powered to detect a difference between groups.
• Smoking cessation. Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A moderate-sized clinical study in adults in India with a history of smoking 5 or more cigarettes daily for at least 3 years shows that taking a specific combination product containing ginger 50 mg, ashwagandha, cowhage, turmeric and other herbal extracts (Smotect, Smotect India) twice daily for 3 months reduces the number of cigarettes smoked by approximately 3 per day when compared with placebo. This product also reduces levels of alveolar carbon monoxide and carboxyhemoglobin but does not improve lung capacity (112115). However, only data from patients who completed treatment were analyzed, which limits the validity of this study. It is also unclear if these effects are due to ginger, other ingredients, or the combination.
• Swallowing dysfunction. The effects of oral ginger for treating swallowing dysfunction are inconclusive. Reasons for the conflicting findings may relate to the route of administration or the number of treatments provided. Details: Clinical research shows that applying a spray containing ginger and clematix root (Tongyan) to the oropharynx for 28 days is more effective than placebo at treating grade 2 or 3 dysphagia in stroke victims. However, there does not seem to be a beneficial effect in patients with grade 1 dysphagia (20342). Other clinical research in elderly patients with dysphagia shows that taking a single dose of ginger 2 mg orally does not improve swallowing but increases saliva (96671). It is possible that a single dose of ginger is not enough to improve swallowing function.
• Toxin-induced liver damage. Oral ginger might help to prevent liver damage in patients using antimycobacterial drugs. Details: Preliminary clinical research shows that a specific ginger supplement (Zintoma, Goldaru) 500 mg taken 30 minutes prior to antimycobacterial drugs daily for 4 weeks reduces the percentage of patients experiencing an increase in liver function enzymes to greater than five times the upper limit of normal by 54% when compared with placebo. Antimycobacterial drugs used for tuberculosis in the study included isoniazid 5 mg/kg, rifampin 10 mg/kg, ethambutol 15 mg/kg, and pyrazinamide 25 mg/kg daily (96670).
• Traumatic brain injury (TBI). Oral ginger has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary research in young adults with subjective memory dysfunction associated with mild TBI, shows that taking a combination of ginger 36 mg and boswellia 360 mg (Memoral) every 8 hours orally for one month improves scores for some, but not all, parameters on an auditory-visual learning test performed at one and three months, when compared with placebo. Total learning scores increased by about 7.5 points with the ginger combination product, compared with 4 points for placebo (110132). It is unclear if these effects are due to ginger, boswellia, or the combination.
• Ulcerative colitis. It is unclear if oral ginger is beneficial for improving symptoms of ulcerative colitis. Details: Preliminary clinical research in adults with ulcerative colitis shows that taking ginger powder 1000 mg twice daily for 12 weeks improves disease activity as measured by the Simple Clinical Colitis Activity Index Questionnaire when compared with taking placebo. However, taking ginger did not improve quality of life, stool frequency, bowel distress, or flatulence when compared with placebo (100694). It is possible that this study was not adequately powered to detect a difference in these secondary outcomes.
• Upper respiratory tract infection (URTI). Although there has been interest in using oral ginger for various upper respiratory tract infections, there is insufficient reliable information about the clinical effects of ginger for this condition.
• Vertigo. It is unclear if oral ginger is beneficial for improving symptoms of vertigo. Details: A small clinical study shows that taking 1 gram of ginger orally as a single dose prior to stimulated vertigo seems to reduce symptoms of vertigo, including nausea, when compared with placebo. However, it does not seem to reduce nystagmus (7623). More evidence is needed to rate ginger for these uses.

(Read more about GINGER)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Bronchitis. Although there has been interest in using inhaled juniper essential oil for bronchitis, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Cancer. Although there has been interest in using oral juniper for cancer, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Diabetes. Although there has been interest in using oral juniper for diabetes, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Dyspepsia. Although there has been interest in using oral juniper for dyspepsia, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Flatulence. Although there has been interest in using oral juniper for flatulence, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Gastroesophageal reflux disease (GERD). Although there has been interest in using oral juniper for GERD, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Kidney stones (nephrolithiasis). Although there has been interest in using oral juniper for nephrolithiasis, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Intestinal parasite infection. Although there has been interest in using oral juniper for intestinal parasite infection, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Rheumatoid arthritis (RA). Although there has been interest in using topical juniper for RA, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Urinary tract infections (UTIs). Although there has been interest in using oral juniper for UTIs, there is insufficient reliable information about the clinical effects of juniper for this purpose.
• Wound healing. Although there has been interest in using topical juniper for wound healing, there is insufficient reliable information about the clinical effects of juniper for this purpose. More evidence is needed to rate juniper for these uses.

(Read more about JUNIPER)

POSSIBLY EFFECTIVE

• Anxiety. Orally, lavender seems to improve anxiety in some patients. Lavender oil aromatherapy and aromatherapy massage also seem to improve chronic and situational anxiety in some patients. Details: Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that lavender essential oil at doses of 80-160 mg daily or dried lavender flower at doses of 500-1500 mg twice daily is provisionally recommended for monotherapy or adjunctive use in the treatment of generalized anxiety disorder. Essential oil capsules and standardized dried flower formulations are preferred over tea preparations (110318). Additionally, guidelines from the American Society of Clinical Oncology and the Society for Integrative Oncology provide a weak recommendation for the use of lavender essential oil inhalation in people with cancer procedure-related anxiety. The recommendation is based on low-quality evidence (114626,114642). Most meta-analyses and clinical trials in patients with subthreshold anxiety, mixed anxiety and depressive disorder, generalized anxiety disorder, and mild to severe anxiety show that taking capsules containing a specific lavender oil ingredient (Silexan, Dr Willmar Schwabe GmbH & Co. KG) 80-160 mg orally daily for 6-10 weeks improves objective and subjective measures of anxiety and increases response rates and complete remission rates when compared with placebo. However, heterogeneity and small sample sizes limit the validity of these findings (58077,58080,58098,95640,97257,103061,103069,112255,114628). Subgroup analyses of 5 clinical studies suggest that Silexan is more effective in older adults with higher somatic symptom burden and those with anxiety-related difficulties in concentration and poor memory at baseline (112255). Additionally, an individual patient-level analysis of 5 clinical studies shows that while Silexan is beneficial in mild to severe anxiety, treatment effects may be more pronounced in those with greater severity at baseline (114628). Limited research has compared Silexan to some conventional prescription medications. One clinical study shows that taking Silexan 80 mg daily for 6 weeks improves anxiety and quality of sleep similarly to low-dose lorazepam 0.5 mg in adults with generalized anxiety disorder (58077). Another clinical study in adults with generalized anxiety disorder shows that taking Silexan 80-160 mg daily for 10 weeks reduces symptom severity similarly to paroxetine 20 mg daily (93004). A network meta-analysis suggests that the higher dose of Silexan (160 mg) might be more effective when compared with paroxetine 20 mg or lorazepam 0.5 mg (103069). Limited research has assessed other oral formulations of lavender. A small clinical study in postmenopausal adults with mild to moderate anxiety shows that taking a dried lavender flower powder 500 mg twice daily for 8 weeks reduces anxiety by about 6% when compared with placebo, as measured on the State-Trait Anxiety Inventory Scale (97256). The clinical significance of this improvement is not clear. Lavender aromatherapy has also been evaluated. Meta-analyses of clinical trials in adults with chronic or situational anxiety show that inhalation aromatherapy or aromatherapy massage using lavender oil moderately reduces anxiety when compared with control. Most often, the control group received no intervention although occasionally they received standard or routine care. In some studies, plain water or diluted lemon juice were used as controls. Most treatments with lavender aromatherapy were given as single sessions of 1-30 minutes. However, occasionally multiple sessions were used (101720,103061,109974). A meta-analysis of 5 clinical studies in adults undergoing hemodialysis shows that aromatherapy with 2% to 100% lavender oil reduces anxiety when compared with control groups receiving no intervention (114625). Most other individual clinical trials of aromatherapy with lavender, alone or in combination with bergamot, are in agreement with these findings (58103,95637,97258,99713,101722,101724,108752,109854,109981), although some research does not support the use of lavender aromatherapy for anxiety (29504,58053,97258,101724,109853). The poor quality of most of the available research makes it difficult to determine which patients, if any, are most likely to benefit.
• Depression. Oral lavender, in the form of tea, tincture, powder, or a specific oil (Silexan), seems to reduce depressive symptoms in some adults. Clinical research also shows that lavender oil aromatherapy may improve symptoms of depression. Details: Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that lavender essential oil at doses of 80-160 mg daily or dried lavender flower at doses of 500-1500 mg twice daily is weakly recommended for monotherapy or adjunctive use in the treatment of major depressive disorder (MDD) (110318). Essential oil capsules and standardized dried flower formulations are preferred over tea preparations. A meta-analysis of five clinical trials shows that oral lavender is moderately more beneficial than a control group for reducing symptoms of depression (109860). Most studies included in the analysis were low- to moderate-quality with variation in patient demographics. Studies in the analysis investigated the effects of oral lavender oil or powder in menopausal or postpartum adults, or in adults with MDD, and compared lavender with routine care, placebo, medication, or no intervention. Doses have included powdered lavender leaves 1-2 grams daily for 8 weeks, lavender tea made from 2 grams powder per teabag once or twice daily for 2 weeks, and a specific oral capsule containing lavender oil (Silexan, Dr. Willmar Schwabe GmbH & Co. KG) 80 mg daily for 70 days (103060,104433,109860). Some research has compared lavender with traditional antidepressants. A large clinical study in adults with mild to moderate MDD shows that taking Silexan 80 mg daily for 8 weeks reduces symptoms of depression as measured on the Montgomery-Asberg Depression Rating Scale (MADRS), and also improves functional impairment, when compared with placebo. These improvements were similar to those seen in a control group taking sertraline 50 mg daily (114631). Conversely, a small clinical study in adults with mild to moderate MDD shows that drinking 60 drops per day of a 1:5 tincture of lavender appears to be slightly less effective than imipramine 100 mg daily; however, lavender might have some additive antidepressant effects when used in combination with imipramine (9792). The validity of these findings is limited by the small study size. Lavender has also been taken in combination with other products. A small clinical study in adults with depression and anxious distress shows that taking 5 mL of a syrup containing lavender flower extract and Chinese dodder extract twice daily for 6 weeks seems to reduce depression to a similar degree as citalopram 20 mg daily (104437). It is unclear if the benefit is due to lavender, Chinese dodder, or the combination. Lavender oil aromatherapy has also been evaluated. A meta-analysis of nine clinical trials shows that lavender oil aromatherapy is moderately more beneficial than control for reducing symptoms of depression. Most studies included in the analysis were low- to moderate-quality with variation in patient demographics. Studies in the analysis investigated the effects of lavender oil aromatherapy in a variety of populations, and no studies were specific to adults with MDD. Lavender aromatherapy was compared with no intervention, routine care, other aromatherapy oils, or distilled water (109860). A small clinical study in adults with post-stroke depression shows that lavender aromatherapy via microcapsules placed inside of a nonwoven bag under the pillow each night for 4 weeks reduces symptoms of depression when compared with control (114627). However, in hospitalized patients undergoing microvascular breast reconstruction, lavender oil aromatherapy does not improve symptoms of perioperative depression when compared with coconut oil (109853). Lavender oil has also been studied in combination with other oils as aromatherapy. A small clinical study in community-dwelling older adults shows that inhalation or massage with lavender, sweet orange, and bergamot oils twice weekly for 8 weeks improves depressive symptoms in 55% to 65% of patients when compared with a control (98474). Another small clinical study in postmenopausal adults shows that a combination of aromatherapy with lavender and bergamot oils three times daily for 8 weeks along with routine care modestly improves symptoms of depression when compared with routine care alone (109981). It is unclear if any benefit is due to lavender, other ingredients, or the combination.
• Dysmenorrhea. Limited clinical research suggests that lavender oil aromatherapy might reduce dysmenorrhea symptoms. Details: A clinical study in young adults with dysmenorrhea shows that applying 3 drops of lavender oil to a piece of cotton and inhaling for 30 minutes daily for the first 3 days of menstruation modestly reduces pain when compared to inhaling the scent of diluted milk (95635). Another small clinical study in patients with dysmenorrhea shows that applying 3 drops of lavender oil to the hands and inhaling for 5 minutes every 6 hours for the first 3 days of menstruation seems to reduce abdominal pain and backache when compared with inhaling the scent of sesame oil (90510). Lavender oil has also been added to abdominal massage. A clinical crossover study in young females with dysmenorrhea shows that administering a gentle abdominal massage with lavender essential oil for 15 minutes moderately reduces pain immediately after treatment when compared with a massage with petrolatum (58106). It is unclear if the benefit persists after the end of the treatment. Additionally, because all available research has been conducted in the Middle East, it is unclear if these results can be extrapolated to other geographic locations.
• Pain (acute). Most clinical research suggests that lavender aromatherapy modestly reduces acute pain from needle insertion or other procedures in infants and adults. The benefit of oral lavender or lavender aromatherapy for other forms of acute pain is unclear. Details: Lavender oil aromatherapy has shown modest benefit for limiting acute pain in adults undergoing a variety of medical procedures. A meta-analysis of 6 small clinical studies shows that lavender aromatherapy, inhaled or as topical application, reduces the severity of pain experienced with arteriovenous fistula catheter insertion for hemodialysis when compared with control (114632). A clinical study in adults with diabetes shows that topical lavender oil sprayed 3 times on the arm five minutes before insulin injection reduces injection site pain when compared with placebo (112254). Additionally, a clinical study in adults undergoing surgical drain removal shows that administering lavender aromatherapy as 2 drops of lavender oil in the oxygen mask reduces pain similarly to a cold compress and to a greater extent than oxygen alone or a control group receiving no intervention (114633). Clinical research also shows that inhaling 10% lavender oil from a heat lamp for 10-15 minutes prior to gynecological exams reduces pain experienced during the exam when compared with no treatment (95639). However, lavender aromatherapy may not reduce pain related to extracorporeal shockwave lithotripsy (ESWL). A clinical study in adults with kidney stones shows that inhaling 4 drops of diffused lavender oil does not reduce pain or the use of self-administered opioids after ESWL when compared with standard care. These results were unchanged when lavender aromatherapy was combined with music (112258). The validity of these findings is limited by a lack of blinding and the high variability in kidney stone size between groups. Lavender oil aromatherapy also seems to modestly reduce pain in infants undergoing various medical procedures. One clinical study in term infants shows that aromatherapy with lavender oil 0.5% for one minute before vaccination modestly reduces pain and decreases crying time by about 20 seconds when compared with sweet almond oil (109869). Another small clinical study in term infants shows that being placed in an incubator with lavender essential oil scent overnight before receiving a blood draw modestly reduces overall pain scores to a similar extent as 2 mL of 30% glucose solution and to a greater extent than no intervention (103066). A small clinical study in preterm infants shows that inhaling the scent of 6 lavender oil drops on a cotton ball for 3 minutes before and 30 seconds after a heel-lancing procedure reduces pain scores when compared with exposure to an unscented cotton ball (104442). Another small clinical study in preterm infants shows that placing cotton soaked with lavender oil in front of the infant's nose for 5 minutes before and 2 minutes after venipuncture reduces pain intensity during and after venipuncture to a similar extent as cotton soaked in breastmilk but to a greater extent than cotton soaked with distilled water (114638). A small clinical study also shows that applying a gauze pad containing one drop of lavender oil under the nose, starting 2 minutes before frenotomy and continuing throughout the procedure, modestly reduces pain when compared with routine care, which includes swaddling, oral sucrose, and pre-frenotomy sucking. Post-frenotomy crying was also reduced by about 50%, or 10 seconds (109868). Lavender oil seems to be similarly effective to vanilla oil for this purpose (109810).

POSSIBLY INEFFECTIVE

• Cancer-related pain. Using lavender oil for massage or as an aromatherapy diffusion does not seem to provide any additional pain relief in patients with advanced or terminal cancer. Details: Clinical research in patients with advanced or terminal cancer shows that diffusing lavender oil as aromatherapy or using lavender oil for massage does not improve pain scores when compared with control treatments without lavender oil (29504,58053).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alopecia areata. Topical lavender oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with alopecia areata shows that applying lavender oil in combination with essential oils from thyme, rosemary, and cedarwood daily for 7 months seems to improve hair growth in 44% of participants when compared with 15% of those using only carrier oils (5177). It is unclear if this effect is due to lavender oil, other oils, or the combination.
• Atopic dermatitis (eczema). Although there is interest in using topical lavender oil for eczema, there is insufficient reliable information about the clinical effects of lavender oil for this condition.
• Burns. It is unclear whether lavender oil aromatherapy is beneficial as adjunct treatment for reducing pain associated with dressing changes in children with burns. Details: Preliminary clinical research in young children with second-degree burns shows that lavender oil aromatherapy, provided as 0.5 mL dripped onto a gauze pad and placed 20 cm away from the child's nose for 15 minutes before a dressing change, modestly reduces pain severity at 1 and 30 minutes after the dressing change when compared with placebo aromatherapy with jojoba oil. Use of lavender oil aromatherapy also attenuated increases in heart and respiratory rates after the dressing change (109857).
• Canker sores. Topical lavender oil might improve canker sore healing and reduce swelling and pain. Details: A clinical study shows that applying 2 drops of lavender oil to canker sores three times daily might reduce redness, swelling, and pain when compared with placebo (58099).
• Colic. Two clinical studies suggest that lavender oil, applied topically during massage of the belly or inhaled as aromatherapy, might modestly reduce duration of crying in infants with colic. Details: A small clinical trial shows that using lavender oil diluted with almond oil to massage the belly of infants for 5-15 minutes beginning at the onset of colic reduces average weekly crying times by about 7 hours when compared with infants not receiving aromatherapy massages (58096). It is unclear if this effect is due to lavender oil, massage, or the combination. Another moderate-sized clinical study in infants 4-8 weeks old with colic shows that inhaling lavender oil as aromatherapy for 4-6 hours daily for 7 days reduces the duration of night crying when compared with placebo (112260).
• Coronary artery bypass graft (CABG) surgery. Small clinical studies suggest that lavender aromatherapy might modestly improve sleep and reduce pain in patients who have undergone CABG surgery. Details: One small clinical study shows that placing three drops of lavender oil (Barich Essence Company) on the pillow every night for 5 nights modestly improves sleep quality, but not sleep latency, duration, or efficiency, when compared with placebo (109861). Another small clinical study shows that placing 2 drops of lavender oil on a cotton ball for overnight aromatherapy starting on the second evening after surgery modestly improves sleep quality on the second and third nights of use, but not the first night, when compared with distilled water (109856). Also, a small clinical study shows that applying 5 drops of lavender oil 20% to a gauze which is worn around the neck for 30 minutes after CABG surgery modestly reduces postoperative pain on the day of surgery and the day after surgery when compared with pre-aromatherapy pain levels. These changes were greater than those seen in patients inhaling distilled water (109850). However, one small clinical study shows that inhaling 2 drops of lavender oil 2% for 20 minutes on postoperative days 2 and 3 does not reduce mental stress when compared with placebo (93009).
• Coronavirus disease 2019 (COVID-19). It is unclear if oral lavender is beneficial for improving the symptoms of mild to moderate COVID-19. Details: A small clinical trial in adults with olfactory dysfunction related to COVID-19 shows that taking lavender syrup 9 mL twice daily for 3 weeks in combination with routine treatments modestly reduces symptoms when compared with routine treatments alone. However, there was no change in symptom scores or the percentage of participants with complete improvement in olfactory or taste dysfunction. The lavender syrup was made by preparing a water extract of the dried aerial parts and mixing with honey and water (109864). A clinical study in adults with mild to moderate respiratory symptoms, suspected by not confirmed to be caused by COVID-19, shows that taking lavender syrup 9 mL twice daily for 3 weeks with standard care reduces severity of cough and anosmia, but not anxiety or any other respiratory symptoms, when compared with standard care alone (114635). The interpretation of these results is limited by the lack of a placebo group and the lack of confirmation of COVID-19 infection.
• Dementia. Small clinical studies suggest that diffused aromatherapy with lavender oil may modestly improve agitation symptoms in patients with dementia; however, lavender oil applied to the patient or the patient's clothes might not be beneficial. Details: Some small and heterogeneous clinical studies in patients with dementia show that applying lavender oil aromatherapy via a diffuser for either 20 minutes twice daily, 2 hours daily, or once nightly for up to 3 weeks seems to improve agitation when compared with baseline, water, or a sunflower oil placebo (16393,58052,95632). However, using aromatherapy that is applied to the person's clothes or arms does not seem to help. Small clinical studies in patients with moderate or advanced dementia show that applying lavender oil to a pad attached to a patient's shirt does not reduce agitation when compared with placebo (12213,99710). Another clinical study in nursing home residents with dementia and frequent agitated behavior shows that applying 1 mL of 30% lavender oil to each forearm does not reduce agitation or improve mood when compared with applying placebo oil (93014).
• Diabetic neuropathy. It is unclear if lavender aromatherapy massage is beneficial for diabetic neuropathy. Details: Preliminary clinical research in patients with neuropathic pain related to diabetes shows that a gentle foot massage with lavender essential oil 3% in sunflower oil for 10 minutes nightly for 1 month reduces neuropathic pain and improves quality of life when compared with a placebo sunflower oil massage or routine care alone (109858).
• Fall prevention. It is unclear if lavender aromatherapy prevents falls in elderly patients. Details: A clinical study in nursing home residents aged 65 years or older shows that attaching a patch with lavender oil (Aromaseal Lavender, Hakujuji Co.) onto the neckline of clothing once daily for one year seems to have a non-significant trend toward reduced fall incidence when compared with placebo (58101).
• Fatigue. Small clinical studies suggest that lavender aromatherapy may modestly reduce fatigue in patients with underlying medical conditions, such as kidney failure or heart disease. The effects of lavender for fatigue in otherwise healthy adults is unclear. Details: Most, but not all, small clinical studies in adults with kidney failure show that receiving aromatherapy with lavender essential oil during hemodialysis sessions for 4 weeks reduces fatigue when compared with baseline, a control group, or a placebo group (95642,98524,109867). A meta-analysis of 5 clinical studies in patients undergoing hemodialysis shows that aromatherapy with 5% to 100% lavender essential oil reduces fatigue when compared with control groups inhaling almond oil or receiving no intervention (114625). Lavender aromatherapy has also been tried in patients hospitalized with various forms of cardiac disease. A small clinical trial shows that placing 3 drops of lavender oil on a cotton ball and inhaling for 20 minutes nightly for 7 days improves fatigue scores by 21 points, compared with a 2-point improvement in those receiving placebo (107959). The validity of these findings is limited due to the short duration of treatment.
• Hypertension. Lavender has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in adults with mild hypertension shows that aromatherapy with lavender oil 0.3% and ylang ylang oil 0.7%, provided via a fabric sticker placed on participant shirt collars, modestly reduces systolic blood pressure after 3 days of use and heart rate after 14 days of use when compared with control stickers containing no essential oils (114641).
• Insect repellent. Although there is interest in using topical lavender to repel insects, there is insufficient reliable information about the clinical effects of lavender for this condition.
• Insomnia. Inhalation aromatherapy or aromatherapy massage with lavender oil may improve some subjective measures of sleep, but results are conflicting and improvements appear minimal at best. Additionally, most small clinical studies suggest it does not improve sleep in hospitalized patients. Details: Lavender oil aromatherapy seems to improve sleep quality in some patients, although it is unclear which patient populations may be most likely to be benefit. A clinical study in healthy college students with self-reported sleep problems shows that wearing a patch containing lavender oil 55 mcL on the chest, in addition to practicing sleep hygiene, improves self-reported sleep quality, but not sleep quantity, when compared with wearing a placebo patch (93012). Another small clinical study in elderly patients that have trouble sleeping in nursing homes shows that placing 2 drops of lavender oil to a cotton pad on a nightstand at bedtime for 4 weeks moderately improves sleep quality and reduces fatigue when compared with control (103062). A meta-analysis of three clinical trials shows that lavender modestly improves postpartum sleep quality when compared with control, including placebo or no intervention. However, each trial used a different form of lavender, including a topical cream, a tea, and aromatherapy. Also, the individual trials included in the analysis show that only the cream and aromatherapy resulted in statistically significant improvements in sleep quality (109866). Conversely, a small clinical study in postmenopausal adults with insomnia who received sleep hygiene guidance shows that inhaling lavender oil 6% before bed nightly for 1 month does not improve sleep quality when compared with sunflower oil. The oil was inhaled from the bottle for two, two-minute sessions and then poured on a cotton ball and placed near the head while sleeping (109852). Lavender aromatherapy has also been evaluated for insomnia in patients with comorbid disease states. A clinical study in patients with insomnia and type 2 diabetes shows that lavender oil aromatherapy for 5 minutes at bedtime nightly for 4 weeks improves sleep when compared with almond oil (103065). Preliminary clinical research in adults with kidney failure shows that foot massage with lavender oil 1.5% for 3 weeks during hemodialysis modestly improves sleep quality when compared with routine care, but is no more effective than sweet orange oil (109859). Another small clinical study in cancer patients shows that receiving aromatherapy as two drops of pure lavender oil applied to a cotton ball and attached to the collar for 20 minutes at bedtime for one week improves sleep when compared with baseline, but seems to be no better than using peppermint oil or a lavender oil 1% control (103063). The validity of this finding is limited because the lavender oil 1% control resulted in notable benefit and might have been an inadequate control treatment. Additionally, a small clinical study in adults with post-stroke depression shows that lavender aromatherapy via microcapsules placed inside of a nonwoven bag under the pillow each night for 4 weeks improves sleep quality, latency, and duration when compared with control (114627). Aromatherapy with lavender oil does not seem to improve sleep in most hospitalized patients, including patients in intermediate care units, hospitalized cardiac patients, and in patients undergoing microvascular breast reconstruction. Aromatherapy treatments have included lavender aromatherapy throughout hospitalization, placing 3 mL of lavender oil 3 feet away from the bed during sleep, and hand and lower leg massage with lavender essential oil 1.5% in sweet almond oil at bedtime (93013,101727,109853). However, studies have generally been small and did not use proper controls. Also, some small clinical studies suggest that lavender aromatherapy might have modest beneficial effects in patients undergoing coronary artery bypass graft (CABG) surgery (109856,109861).
• Kidney failure. Small clinical studies suggest that lavender aromatherapy may modestly reduce fatigue and improve sleep quality in adults receiving hemodialysis. Lavender oil massage may also modestly improve symptoms of restless leg syndrome (RLS) in these patients. Details: Multiple small studies have evaluated lavender aromatherapy, provided during hemodialysis sessions, for reducing fatigue. A small clinical study shows that applying 5% lavender essential oil (Barij Essence Pharmaceutical Company) to a cotton ball on the patient's collar for inhalation for 15-20 minutes twice daily during each session for 1 month reduces fatigue by an additional 44% and 40% when compared with baseline and control, respectively (98524). Another preliminary clinical trial shows that applying lavender oil 7% in sweet almond oil to a gauze pad placed 20 cm from the patient's nose for 2 minutes improves fatigue when compared with placebo aromatherapy. By the third week of four total weeks of treatment, most patients given lavender oil aromatherapy had only mild fatigue, compared with moderate or severe fatigue in the control group (109867). Also, a small clinical trial shows that aromatherapy or aromatherapy foot massage with lavender and sweet orange oil for 10-20 minutes during each session for 2 months reduces fatigue when compared with no treatment. Aromatherapy massage seems to be more effective than aromatherapy alone (103068). However, one small clinical study shows that applying the oil for inhalation for 10 minutes during each session for 1 month does not reduce fatigue when compared with control (95642). The difference in these findings might be due to study size, lavender oil concentration, or the frequency and duration of aromatherapy sessions. Lavender aromatherapy has also been evaluated for reducing insomnia in adults on hemodialysis. A small clinical study shows that foot massage with lavender oil 1.5% for 3 weeks during hemodialysis sessions modestly improves sleep quality when compared with routine care. However, it does not seem to be more effective than using sweet orange oil (109859). Some small clinical studies in patients undergoing hemodialysis show that massaging the feet or lower legs with lavender oil reduces the severity of RLS by up to 45% when compared with routine care, massage only, or baby oil as placebo (95638,103064,109865). However, massage with lavender oil does not seem to be more beneficial than glycerin oil 2% or sweet orange oil 1.5% for reducing RLS severity (103064,109859). Doses have included 10-15 mL of 1.5% or 5% lavender oil for 10- to 45-minutes during hemodialysis sessions for 3-4 weeks (95638,103064,109859,109865).
• Labor pain. Small studies suggest that lavender oil aromatherapy may help to modestly reduce pain during childbirth. Details: A meta-analysis of clinical trials in Iran shows that lavender oil aromatherapy applied by various means, such as mask or massage, reduces labor pain when compared with control (104440). All included studies were conducted in Iran, so it is unclear if the benefit can be extrapolated to other geographic locations.
• Lice. Topical lavender oil has only been evaluated in combination with other essential oils; its effect when used alone is unclear. Details: Clinical studies in patients with head lice shows that applying lavender oil in combination with tea tree oil reduces the number of hatched and unhatched live lice when compared with control (19188,19189). When applied with tea tree oil three times weekly, lavender oils seems to improve lice eradication when compared with two weekly treatments of pyrethrin and piperonyl butoxide (19189). It is not known if these effects are due to tea tree oil, lavender, or the combination.
• Menopausal symptoms. It is unclear if either lavender aromatherapy or oral lavender reduce menopausal symptoms such as hot flashes. Details: A meta-analysis and individual clinical studies in postmenopausal adults show that lavender aromatherapy for 4-12 weeks, alone or in combination with other essential oils, reduces menopausal symptoms such as hot flashes when compared with placebo (95634,99711,103067). However, heterogeneity and small sample sizes limit the validity of these findings. A small clinical study in postmenopausal adults shows that aromatherapy with lavender 2% oil for 20 minutes at bedtime every day for 1 month improves quality of life scores when compared to baseline (99711). Another small clinical study in menopausal adults shows that receiving aromatherapy with lavender oil and lemon oil for 5 minutes daily for 30 days seems to improve sleep and quality of life when compared with placebo (104439). However, a small clinical study in postmenopausal adults shows that a combination of lavender and bergamot oils administered via inhalation three times daily for 8 weeks with routine care does not improve sexual function when compared with routine care alone (109981). Oral lavender has also been evaluated for improving menopausal symptoms. A small clinical study in postmenopausal adults shows that taking lavender essential oil 80 mg daily by mouth for 2 months does not improve overall menopausal symptom scores when compared with placebo. Although it modestly improved symptoms of sexual dysfunction, it did not improve other vasomotor, physical, or psychological menopausal symptoms when compared with placebo (114629).
• Migraine headache. It is unclear if lavender aromatherapy improves migraine symptoms. Details: A small clinical study in patients with migraine headaches shows that rubbing 2-3 drops of lavender oil on the upper lip for inhalation might reduce headache pain and associated symptoms such as nausea and photophobia. Of 129 headaches treated with lavender oil, 92 responded completely or partially, compared with 32 of 68 headaches in the placebo group (18209).
• Multiple sclerosis (MS). It is unclear if lavender aromatherapy can improve memory in patients with MS. Details: A small preliminary clinical trial in patients with MS shows that dripping 2 drops of lavender oil (Barij Essence Pharmaceutical Company) on a cotton ball for inhalation for 10 minutes twice daily for 2 weeks improves working memory by a small amount when compared with inhaling distilled water (109855).
• Multiple sclerosis-related fatigue. It is unclear if oral lavender or lavender aromatherapy is beneficial for reducing fatigue in adults with multiple sclerosis (MS). Details: A small clinical trial in adults with MS shows that taking lavender 600 mg three times daily for 60 days improves fatigue by a large amount when compared with placebo (109851). Another small clinical study in adults with MS living in Turkey shows that lavender aromatherapy, provided as 3 drops of lavender oil on cotton pads placed 15-20 cm from the bed pillow nightly for 30 days, reduces fatigue severity and improves sleep quality when compared with no intervention (114630).
• Neuropathic pain. Although there is interest in using topical lavender oil for neuropathic pain, there is insufficient reliable information about the clinical effects of lavender for this condition.
• Osteoarthritis. It is unclear if lavender aromatherapy with massage reduces osteoarthritis pain. Details: A small clinical study in patients with osteoarthritis shows that applying 5 mL of 3% lavender oil (Barij Essence Pharmaceutical Company) to the knee through self-administered massage three times weekly for 3 weeks can reduce pain by 23% when compared to massage with placebo oil and by 36% when compared with no treatment. However, any benefits of treatment begin to wear off after treatment completion (95645).
• Otitis media. Topical lavender oil has only been evaluated in combination with other essential oils; its effect when used alone is unclear. Details: A clinical study in children ages 5-18 years with otitis media and otalgia shows that administering ear drops containing lavender and other herbal extracts, alone or in combination with a topical anesthetic, improves ear pain when compared with baseline. However, it is possible that the pain is self-limited and any pain reduction is due to natural resolution (39500).
• Perioperative anxiety. It is unclear if lavender aromatherapy is beneficial for perioperative anxiety. Details: A large clinical study in adults shows that inhaling lavender 2% before, during, and after dental procedures reduces dental pain intensity and perioperative dental anxiety when compared with control. Inhaled lavender seems to have the greatest effect on perioperative anxiety when used in the waiting room (112250). Conversely, a clinical study in adults with kidney stones undergoing extracorporeal shockwave lithotripsy (ESWL) shows that inhaling 4 drops of diffused lavender oil does not reduce anxiety when compared with standard opioid analgesia. These results were unchanged when lavender aromatherapy was combined with music (112258). The validity of these effects is limited by a lack of blinding and the high variability in kidney stone size between groups. Lavender has also been evaluated in combination with other ingredients. A clinical study in adults undergoing port catheter placement under modified anesthesia shows that preoperative and intraoperative placement of an aromatherapy patch containing lavender and peppermint essential oils (Elequil Aromatabs, Beekley Corporation) near the head does not reduce benzodiazepine or opioid requirements or time to discharge when compared with a placebo patch (114623). It is unclear if the use of an oxygen mask during the procedure resulted in inadequate exposure to the aromatherapy oils.
• Polycystic ovary syndrome (PCOS). It is unclear if lavender is beneficial for PCOS. Details: A small clinical study in adults with PCOS between the ages of 18-45 who had not received any prior treatment for the condition shows that taking lavender 250 mg twice daily for 90 days increases serum progesterone levels and reduces menstrual cycle length similarly to metformin 500 mg three times daily (114634).
• Postdural puncture headache. It is unclear if lavender aromatherapy improves postdural puncture headache severity. Details: A small clinical study in adults with postdural puncture headache shows that receiving lavender oil aromatherapy for 15 minutes modestly improves pain immediately after treatment when compared with placebo. However, the pain relief is not maintained at 30 minutes after treatment (104441).
• Postherpetic neuralgia. It is unclear if lavender aromatherapy is beneficial for alleviating pain in postherpetic neuralgia. Details: A small clinical study in adults with postherpetic neuralgia shows that aromatherapy with either lavender oil 1% or oils containing two of its major constituents (linalool 1% or linalyl acetate 1%), placed on gauze and then inhaled with natural breathing for 5 minutes, reduces the intensity and severity of pain when compared with almond oil control (114624). The validity of this finding is limited by the short-term nature of the study; any benefit beyond 5 minutes was not evaluated.
• Postoperative nausea and vomiting (PONV). It is unclear if lavender aromatherapy reduces PONV. Details: A small clinical study in postoperative patients shows that inhaling the scent of 2 drops of lavender oil from a cotton pad for 5 minutes improves nausea scores in 83% of people, compared with 44% of those inhaling a placebo. There was no difference in vomiting scores between groups (99712). Another small clinical study in patients after percutaneous nephrolithotomy shows that inhaling the scent of 3 drops of lavender essential oil from a gauze for 5 minutes immediately after the operation, and again 3 and 6 hours later, does not improve nausea or vomiting when compared with a control group that was not receiving aromatherapy (103872). A specific combination patch providing both lavender and peppermint essential oils (Elequil Aromatabs, Beekley Corporation) has also been evaluated, with conflicting findings. A clinical study in adults undergoing port catheter placement under modified anesthesia shows that preoperative and intraoperative placement of this patch near the head does not reduce antiemetic requirements, the proportion of patients requiring antiemetics, or average PONV scores when compared with a placebo patch (114623). It is unclear if the use of an oxygen mask during the procedure resulted in inadequate exposure to the essential oils. Conversely, a small clinical study in patients with anxiety prior to primary unilateral total hip arthroplasty shows that placement of this patch on the gown at least 1 hour before surgery, with re-application every 12 hours postoperatively for 2 days, reduces PONV on postoperative day 2 when compared with a placebo patch (114622). It is unclear if this effect is due to lavender, peppermint, or the combination.
• Postoperative pain. The evidence for the use of lavender aromatherapy for pain after various types of surgical procedures is conflicting. Details: Some small clinical studies in patients post-Cesarean section shows that, when used in conjunction with standard analgesic therapy, applying 2 drops of lavender oil 2% to a face mask or applying 3 drops of lavender to a cotton ball for inhalation modestly reduces postoperative pain when compared with control (58093,101724). A small clinical study in adults undergoing coronary artery bypass graft (CABG) surgery shows that applying lavender oil to a gauze which is worn around the neck may modestly reduce postoperative pain on the day of surgery and the day after surgery when compared with distilled water (109850). However, aromatherapy with lavender throughout hospitalization does not seem to improve postoperative pain in patients undergoing microvascular breast reconstruction when compared with coconut oil (109853). Additionally, a clinical study in adults hospitalized after abdominal surgery shows that a lavender oil-infused warm water foot bath for 20 minutes each night for 3 nights after surgery does not reduce postoperative pain when compared with a standard warm water foot bath (114637). Likewise, a clinical study in adults hospitalized after total knee or hip arthroplasty shows that lavender aromatherapy administered via inhalers and used as needed does not reduce pain or analgesic use when compared with control (114639). Lavender oil aromatherapy has also been evaluated in children. A small clinical study in children aged 6-12 years post-tonsillectomy shows that rubbing lavender oil onto the palms and inhaling for 3 minutes every 6 hours as needed reduces acetaminophen use when compared with control (90513). A specific combination patch providing both lavender and peppermint essential oils (Elequil Aromatabs, Beekley Corporation) has also been evaluated, with conflicting findings. A clinical study in adults undergoing port catheter placement under modified anesthesia shows that preoperative and intraoperative placement of the patch near the head does not reduce time to readiness for discharge, opioid requirements, or pain intensity scores when compared with a placebo patch (114623). It is unclear if the use of an oxygen mask during the procedure resulted in inadequate exposure to the essential oils. Conversely, a small clinical study in patients with anxiety prior to primary unilateral total hip arthroplasty shows that placing the patch on the gown at least 1 hour before surgery, with re-application every 12 hours postoperatively for 2 days, reduces opioid use on postoperative day 2, as well as pain scores and acetaminophen use on postoperative day 7, when compared with a placebo patch (114622). It is unclear if any effect is due to lavender, peppermint, or the combination.
• Postpartum complications. It is unclear if topical or inhaled lavender reduces postpartum complications such as pain and swelling. Details: Some clinical research in patients receiving an episiotomy during childbirth shows that adding lavender oil to water or sitz baths for up to 10 days might reduce episiotomy redness and discomfort when compared with using no lavender and standard treatment, such as povidone-iodine. However, findings are mixed as to whether adding lavender oil to baths helps to reduce edema and analgesic use (58085,58092,58116,58121). Lavender aromatherapy has also been studied to improve wellbeing in postpartum patients. A small clinical study in postpartum patients immediately following a natural birth shows that inhaling lavender oil from a cotton ball for 10-15 minutes in the morning, 6 hours later, and at bedtime, improves perceived pain, fatigue, distress, and mood within 1 hour of treatment and also the next morning when compared with placebo (95631).
• Postpartum depression. Small clinical studies suggest that aromatherapy with lavender oil may modestly improve or prevent depressive symptoms in postpartum patients. Details: A clinical study in healthy postpartum patients shows that placing 3 drops of lavender essential oil on the palms three times daily for 4 weeks after delivery moderately reduces depressive symptoms and anxiety when compared with usual care only (95637). There is limited research on the benefits of lavender aromatherapy in patients diagnosed with postpartum depression. A small clinical trial in these patients shows that a combination of lavender and rose essential oils, administered via inhalation or aromatherapy massage using hand "M" technique for 15-minute sessions, twice weekly for 4 weeks, reduces depression scores when compared with no intervention (58103).
• Pre-procedural anxiety. It is unclear if lavender aromatherapy can reduce preoperative or preprocedural anxiety; results from clinical research are generally of low-quality and benefits are modest at best. Details: A meta-analysis of four small clinical studies in patients undergoing cardiac surgery shows that lavender aromatherapy modestly reduces preoperative anxiety when compared with control (103058). Similarly, a meta-analysis of 19 small to moderate-sized clinical studies in adults undergoing various types of surgical procedures shows that lavender aromatherapy modestly reduces preoperative anxiety when compared with routine care or placebo (114636). However, most of the studies included in these meta-analyses were conducted in the Middle East, and it is unknown if these results are generalizable to other geographic areas. There is conflicting clinical evidence regarding the effect of lavender aromatherapy on anxiety prior to a dental procedure (58078,101725,103059). Small clinical studies also show mixed results as to whether lavender oil aromatherapy applied to a gauze bandage or oxygen mask improves anxiety in patients waiting for breast surgery when compared with usual care. (95641,101729). Lavender aromatherapy might reduce anxiety prior to less risky and extensive procedures such as needle injections. Small clinical studies in adults receiving botulinum toxin type A injections or children receiving dental injections show that lavender oil aromatherapy reduces heart rate and cortisol levels when compared with placebo (58089,104438). Another clinical study in preoperative patients undergoing insertion of a peripheral venous cannula shows that inhalation of 1% lavender oil from a gauze pad for 5 minutes modestly reduces pain and anxiety scores and improves patient satisfaction when compared with control (95636). However, a clinical study in patients undergoing a colonoscopy or esophagogastroduodenoscopy shows that inhaling lavender oil does not reduce anxiety, although it does improve patient satisfaction, when compared with placebo (58066). Reasons for conflicting findings are unclear but may relate to the severity of anxiety, the specific outcomes measured, and cultural differences occurring in different geographic locations.
• Pruritus. Topical lavender has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in older females with pruritus shows that aromatherapy massage utilizing a 4:1:1 mixture of lavender, Roman chamomile, and sandalwood oils diluted to 1.5% in sweet almond oil, three times weekly for 1 month, modestly improves pruritus and reduces pruritus-related stress when compared with sandalwood oil alone. However, it does not improve skin pH or level of hydration (112365). It is unclear if these findings are due to lavender, other ingredients, or the combination.
• Psychological well-being. It is unclear if topical or inhaled lavender improves well-being. Details: A small clinical study in healthy females shows that adding 3 mL of a mixture containing 20% lavender oil and 80% grapeseed oil to daily baths modestly improves mood when compared with baths containing grapeseed oil alone (15534). However, lavender may not impact well-being in patients with cancer. Clinical research shows that that adding lavender oil for an aromatherapy massage in patients with advanced or terminal cancer does not improve well-being or quality of life when compared with no massage treatment or massage with inert oil (29504,58053).
• Restless legs syndrome (RLS). Most small clinical studies suggest that lavender oil aromatherapy massage may be beneficial for RLS in patients undergoing hemodialysis. Its benefits in other patient populations are unclear. Details: A meta-analysis of small clinical studies in patients undergoing hemodialysis show that massaging the feet or lower legs with lavender oil reduces the severity of RLS by up to 45% when compared with routine care, massage only, or baby oil as placebo (95638,103064,109865,114632). However, massage with lavender oil does not seem to be more beneficial than glycerin oil 2% or sweet orange oil 1.5% for reducing RLS severity (103064,109859). Doses have included 10-15 mL of 1.5% or 5% lavender oil for 10-45 minutes during hemodialysis sessions for 3-4 weeks (95638,103064,109859,109865).
• Stress. Some clinical studies suggest that inhaling lavender oil as aromatherapy may reduce stress. However, overall research is conflicting. Details: A meta-analysis of 21 moderate- to high-quality, small- to medium-sized studies shows that inhaling lavender oil modestly reduces stress when compared with control. Most studies included in the analysis have used lavender oil as aromatherapy; other studies have used a cream (109863). In contrast, a clinical study in pharmacy students shows that inhaling lavender oil 3% in almond oil twice daily for 30 minutes during the exam period does not reduce academic stress or associated symptoms, including headache, blood pressure, or heart rate, when compared with inhaling an odorless oil, although both were more effective than no intervention (101723). Lavender oil aromatherapy has shown conflicting results when evaluated for reducing stress in healthcare professionals. A small study in hospital nurses with work-related stress shows that inhaling lavender oil as aromatherapy for 2 hours daily for 4 weeks does not reduce job-related stress when compared with placebo or rose oil aromatherapy (112256). However, another small clinical study in healthcare professionals at an outpatient clinic shows that inhaling lavender oil through a diffuser during work shifts reduces work stress and increases job satisfaction when compared with placebo (112251).
• Toothache. Although there is interest in using topical lavender oil for toothache, there is insufficient reliable information about the clinical effects of lavender oil for this purpose. More evidence is needed to rate lavender for these uses.

(Read more about LAVENDER)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Asthma. Preliminary clinical research in adults shows that taking marjoram oil 2 drops daily for 3 months along with conventional treatment for asthma improves some measures of lung function. Forced vital capacity (FVC) increased by 0.3 mL with marjoram compared to 0.1 mL in the control group. The forced expiratory volume in 1 second (FEV1) increased by 4.1% with marjoram compared to 2.7% with control. While these improvements were statistically significant compared to baseline, statistical analysis between groups was lacking (76944).
• Dysmenorrhea. Preliminary clinical research in women aged 19-45 years with primary dysmenorrhea shows that massaging the lower abdomen with a cream containing lavender, clary sage, and marjoram essential oils (2:1:1 ratio) diluted in unscented jojoba cream to a 3% concentration, in a dose of two grams daily, starting at the end of menstruation and continuing until the beginning of the next, might decrease the level and duration of pain when compared with a placebo cream containing synthetic fragrances. The decrease in pain duration, from 2.4 days to 1.8 days in the essential oils group, was statistically significant when compared to baseline (58095). It is unclear if these effects are due to marjoram, other ingredients, or the combination.
• Parkinson disease. Preliminary clinical research in patients with Parkinson disease who are stabilized on levodopa shows that drinking a tea containing 5 grams of dried marjoram leaf daily for 30 days does not lower Unified Parkinson Disease Rating Scale part III motor scores (USPDRSIII), but does decrease scores on the Non-Motor Symptoms Scale (NMSS) and the Beck Depression Inventory (BDI), when compared with placebo tea (108498).
• Polycystic ovary syndrome (PCOS). Preliminary clinical research shows that drinking marjoram leaf tea 250 mL twice daily for 1 month modestly reduces levels of dehydroepiandrosterone sulfate (DHEA-S) and insulin in women with PCOS. Body weight, fasting glucose, and serum levels of follicle-stimulating hormone, luteinizing hormone, progesterone, and testosterone did not improve (95325). More information is needed to rate marjoram for these uses.

(Read more about MARJORAM)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Cardiovascular disease (CVD). Although there has been interest in using oral Monterey pine for preventing CVD, there is insufficient reliable information about the clinical effects of Monterey pine for this condition.
• Cognitive function. It is unclear if oral Monterey pine bark extract improves cognition. Details: Preliminary clinical research shows that taking vitamin C 120 mg daily along with a specific product containing Monterey pine bark extract (Enzogenol, ENZO Nutraceuticals) 960 mg daily for 5 weeks improves response speed related to working memory tasks and immediate recognition tasks in middle-aged and elderly males when compared with baseline. Improvements in memory do not appear to occur with vitamin C alone (63620).
• Migraine headache. Although there has been interest in using oral Monterey pine for preventing migraine headache, there is insufficient reliable information about the clinical effects of Monterey pine for this condition.
• Neurological trauma. It is unclear if oral Monterey pine bark extract is beneficial in patients with neurological trauma. Details: A small clinical study in patients 3-12 months post-traumatic brain injury shows that taking a specific Monterey pine bark extract (Enzogenol, ENZO Nutraceuticals) 1000 mg daily for 12 weeks improves cognitive function scores when compared with placebo. However, measures of working memory, episodic memory, anxiety, and depression were not improved (105777). Another small clinical study in college students suffering from chronic concussion symptoms shows that taking a specific Monterey pine bark extract (Enzogenol, ENZO Nutraceuticals) 1000 mg daily for 6 weeks improves mental fatigue when compared with placebo (105779). More evidence is needed to rate Monterey pine for these uses.

(Read more about MONTEREY PINE)

POSSIBLY EFFECTIVE

• Memory. Oral rosemary seems to improve memory in young adults. It is unclear if rosemary aromatherapy improves memory. Details: Clinical research in healthy adults shows that taking rosemary 500 mg orally twice daily for one month improves memory by approximately 14% when compared with placebo (98536). Other preliminary clinical research shows that applying four drops of pure rosemary essential oil (Tisserand Aromatherapy) to an aromatherapy diffuser pad 5 minutes before a single test period can improve the quality, but not the speed, of memory recall, and increase alertness and contentment more than lavender aromatherapy or no aroma (18323). Rosemary aromatherapy has also been evaluated for improving memory in adults with kidney failure. A small clinical study in patients (mean age 53 years) undergoing hemodialysis shows that aromatherapy with rosemary essential oil three times weekly for 1 month does not improve medication adherence or measures of prospective and retrospective memory when compared with a control group. In this study, five drops of rosemary essential oil were applied to gauze, which was then placed 10 cm from the patient's nose for 30 minutes starting 1 hour after hemodialysis (109559).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Abortion. Although there has been interest in the use of oral rosemary as an abortifacient, there is insufficient reliable information about the clinical effects of rosemary for this purpose.
• Age-related cognitive decline. It is unclear if oral rosemary is beneficial for age-related cognitive decline. Details: A small clinical study in healthy individuals aged 65-90 years shows that a single 750 mg dose of powdered rosemary leaf in tomato juice may improve memory speed. However, higher single doses of 1500-6000 mg seem to have a deleterious effect on memory speed. For other measures of attention and memory, there were no clear benefits across the range of doses from 750-6000 mg (18246). Oral rosemary has also been evaluated in combination with other ingredients. A small clinical study in healthy adults aged 62 years or younger shows that taking a combination product containing equal parts rosemary, lemon balm, and sage twice daily for 2 weeks modestly improves word recall when compared with placebo. However, it does not appear to have benefit in adults aged 63 years and older (97277). It is unclear if any benefit is due to rosemary, other ingredients, or the combination.
• Alopecia areata. Topical rosemary oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that rosemary oil 114 mg, in combination with lavender oil 108 mg, thyme oil 88 mg, and cedarwood oil 94 mg, mixed with jojoba oil 3 mL and grapeseed oil 20 mL and applied topically to the scalp, improves hair growth in 44% of patients, compared with 15% of those receiving placebo. This combination was massaged into the scalp for a minimum of 2 minutes, followed by wrapping the head in a warm towel, every night for 7 months (5177).
• Androgenic alopecia. It is unclear if topical rosemary is beneficial for androgenic alopecia. Details: Preliminary clinical research shows that applying rosemary oil (Barij Essence Pharmaceutical Company) 1 mL to the scalp twice daily for 6 months is as effective as minoxidil 2% for increasing hair count in patients with androgenic alopecia (91729).
• Depression. It is unclear if oral rosemary is beneficial for major depressive disorder. Details: A small clinical trial among adults newly diagnosed with major depressive disorder and recent initiation of antidepressant medication shows that taking rosemary dried leaf extract 650 mg twice daily for 8 weeks might reduce some symptoms of depression and anxiety when compared with placebo (112141). However, the validity of these findings is limited by differences in baseline depression symptom scores between groups.
• Diabetes. It is unclear if oral rosemary is beneficial for improving glycemic control in patients with type 2 diabetes. Details: In patients with type 2 diabetes, preliminary clinical research shows that taking rosemary tea daily for 90 days decreases glycated hemoglobin levels by 15% and waist and hip circumference by 6% and improves insulin resistance. However, there was no effect on fasting blood glucose, lipid profile, body weight, or body mass index (BMI). The tea was made by adding rosemary 2 grams to a liter of boiling water for 3 minutes and then passing through a sieve (105323). Other preliminary clinical research in adults with type 2 diabetes shows that taking rosemary powder 3 grams daily for 4 weeks does not reduce fasting blood glucose levels or improve lipid profile when compared with baseline. These endpoints were improved in a group of healthy adults (105327). The validity of the findings from these studies is limited by the lack a comparator group.
• Diabetic nephropathy. Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a specific combination product (Canephron N, Bionorica) containing 18 mg each of rosemary leaf, centaury herb, and lovage root per tablet, as two tablets three times daily for 6 months along with standard antidiabetes treatment and enalapril (Vasotec), decreases microalbuminuria by 73%, decreases albumin:creatinine ratio by 46%, increases high-density lipoprotein (HDL) cholesterol by 25%, and lowers triglyceride levels by 43%, but does not improve glomerular filtration rate, when compared to baseline. Improvements were greater in those taking the combination product than in those treated only with standard antidiabetes therapy and enalapril. However, the combination product does not appear to improve reductions in total cholesterol or low-density lipoprotein (LDL) cholesterol (91726).
• Dysmenorrhea. It is unclear if oral rosemary is beneficial for dysmenorrhea. Details: In patients with moderate primary dysmenorrhea, clinical research shows that taking rosemary extract 220 mg every 8 hours for the first three days of the menstrual cycle, repeated for two menstrual cycles, is as effective as mefenamic acid for reducing average pain and bleeding when compared with two baseline cycles (105328).
• Fatigue. Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in healthy young adults with below-average energy levels shows that taking a single dose of a mixture of rosemary from Albania (Rosmarinus officinalis) and Morocco (Rosmarinus eriocalyx) 1.7 grams does not consistently improve sustained attention, motivation to perform cognitive tasks, mental energy, or mental fatigue when compared with placebo (91731).
• Fibromyalgia. Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with fibromyalgia shows that taking an oral product containing rosemary leaf extract, oleanolic acid from olive leaf, and rho iso-alpha acids from hops (Meta050, Metagenics), at a dose of 440 mg three times daily for 4 weeks, then 880 mg twice daily for 4 weeks, does not improve symptoms when compared to baseline (18327).
• Gingivitis. A mouth rinse containing rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults with mild to moderate gingivitis and mild plaque shows that rinsing the mouth with 10 mL of mouthwash containing 5% v/v of a combined alcoholic extract of rosemary, calendula, and ginger for 30 seconds twice daily after meals for 2 weeks decreases plaque formation, gingival inflammation, and gingival bleeding similarly to chlorhexidine gluconate 0.2% mouthwash and better than a placebo mouthwash (93555).
• Hypertension. Although there is interest in using oral rosemary for hypertension, there is insufficient reliable information about the clinical effects of rosemary for this condition.
• Hypotension. It is unclear if oral rosemary is beneficial for hypotension. Details: Preliminary clinical research in patients with primary hypotension shows that taking rosemary essential oil (Metapharmaceutical) 1 mL every 8 hours for 44 weeks increases systolic blood pressure by 13 mmHg and diastolic blood pressure by 7 mmHg when compared to baseline. However, blood pressure returned to near baseline values after treatment discontinuation (91730).
• Mental alertness. It is unclear if rosemary aromatherapy is beneficial for improving mental alertness. Details: Preliminary clinical research in nurses working on a night shift shows that placing one drop of rosemary oil on a surgical mask that is worn for 2 hours with a 10-minute on/15-minute off cycle modestly increases alertness and reduces sleepiness when compared with a water drop control (105324).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral rosemary leaf is beneficial in patients with NAFLD. Details: A small clinical study in patients with NAFLD shows that taking rosemary leaf powder 2 grams twice daily for 8 weeks, in conjunction with diet and exercise recommendations, does not improve measures of liver function, glycemic control, cholesterol, or body weight when compared with placebo (109561).
• Opioid withdrawal. It is unclear if oral rosemary is beneficial for opioid withdrawal when used in combination with methadone. Details: Preliminary clinical research shows that taking rosemary leaf along with methadone for 2 weeks improves symptoms of opioid withdrawal and the ability to sleep when compared with methadone alone after 3 and 7 days of treatment, but not after 2 weeks. Rosemary leaf was provided in capsules containing 300 mg each (Barij Essence Pharmaceutical Company) at a dose of 16 capsules daily for the first 3 days, 12 capsules daily for the next 4 days, and eight capsules daily for the next 7 days, in divided doses (91727).
• Osteoarthritis. Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows subjective reductions in pain associated with osteoarthritis when oral formulations containing rosemary leaf extract, oleanolic acid from olive leaf, and rho iso-alpha acids from hops (NG440-2, Metagenics; Meta050, Metagenics) are used (18326,18327). The formulation used in one of these studies (Meta050, Metagenics) was taken in a dose of 440 mg three times daily for 4 weeks, then 880 mg twice daily for 4 weeks (18327). The formulation used in the other study, which was taken daily for 4 weeks, contained rosemary leaf extract 112.5 mg, oleanolic acid from olive leaf 1 mg, and rho iso-alpha acids from hops 225 mg per tablet (18326).
• Raynaud syndrome. It is unclear if topical rosemary essential oil is beneficial in patients with Raynaud syndrome. Details: A very small, open-label study in patients with Raynaud syndrome caused by systemic scleroderma shows that applying 10 drops of rosemary 10% essential oil to the hands does not increase skin temperature or improve warmth perception when compared with olive oil (109560). However, this study may have been inadequately powered to detect a difference between groups.
• Rheumatoid arthritis (RA). Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows subjective decreases in pain associated with RA when oral formulations containing rosemary leaf extract, oleanolic acid from olive leaf, and rho iso-alpha acids from hops (NG440-2, Metagenics; Meta050, Metagenics) are used (18326,18327). The formulation used in one of these studies (Meta050, Metagenics) was taken in a dose of 440 mg three times daily for 4 weeks, then 880 mg twice daily for 4 weeks (18327). The formulation used in the other study, which was taken daily for 4 weeks, contained rosemary leaf extract 112.5 mg, oleanolic acid from olive leaf 1 mg, and rho iso-alpha acids from hops 225 mg per tablet (18326).
• Stress. It is unclear if rosemary aromatherapy is beneficial for stress. Details: Preliminary clinical research on the use of rosemary aromatherapy for anxiety and stress is conflicting. In a group of graduate nursing students, perceived stress associated with taking a test was lower when inhalers containing rosemary or lavender oil were used. Three drops of rosemary essential oil were added to an inhaler and inhaled before and during the test. Pulse rates, but not blood pressure, were also reduced (18324). In contrast, a small clinical study in adults aged 18-30 years shows that the aroma from diluted rosemary essential oil applied to the wrist during timed crossword puzzle completion actually increases subjective feelings of anxiety and tension when compared with placebo (18325).
• Sunburn. Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a combination of rosemary and grapefruit extracts in a 1:1 ratio (NutroxSun, Monteloeder, Inc.), 250 mg orally once daily for 12 weeks, increases the amount of UV radiation needed to cause sunburn by 34% after 8 weeks and 56% after 12 weeks when compared to baseline (91728). The validity of these findings is limited by the lack of a comparator group.
• Upper respiratory tract infection (URTI). Oral rosemary has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial among healthy adults shows that taking a combination product containing rosemary leaf extract, aloe gel powder, and poria mushroom extract daily for 8 weeks does not reduce the frequency, duration, or severity of URTI-related symptoms when compared with placebo. However, in patients receiving an influenza vaccine midway through the study, this product does seem to improve some immune response biomarkers when compared with placebo (111921). The amount of rosemary leaf extract in the supplement was not disclosed.
• Wound healing. It is unclear if topical rosemary cream is beneficial for wound healing. Details: A moderate-sized clinical trial among primiparous adults with medio-lateral episiotomy shows that applying a cream containing rosemary extract to the wound twice daily for 10 days improves episiotomy wound healing and reduces redness and discharge when compared with placebo cream (112143). More evidence is needed to rate rosemary for these uses.

(Read more about ROSEMARY)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Cancer. Observational research has found that daily intake of oranges and/or tangerines is associated with a reduced odds of developing nasopharyngeal carcinoma when compared with consuming oranges and/or tangerines less than once a week (28608). More evidence is needed to rate tangerine for this use.

(Read more about TANGERINE)

LIKELY SAFE ...when used orally in food amounts. Benzoin has generally recognized as safe (GRAS) status in the US (97997). The maximum concentration recommended as a flavoring in foods is 0.014% (11).

POSSIBLY SAFE ...when benzoin and compound benzoin tincture are used by inhalation (6002). ...when used topically (11). Benzoin can cause contact dermatitis in some people (11,12,103827).

POSSIBLY UNSAFE ...when benzoin and compound benzoin tincture are used orally in medicinal amounts. Accidental oral ingestion of compound benzoin tincture intended for inhalation has been reported to cause gastritis and gastrointestinal hemorrhage (6002).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about BENZOIN)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Black pepper has Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when black pepper oil is applied topically. Black pepper oil is nonirritating to the skin and is generally well tolerated (11). ...when black pepper oil is inhaled through the nose or as a vapor through the mouth, short-term. Black pepper oil as a vapor or as an olfactory stimulant has been used with apparent safety in clinical studies for up to 3 days and 30 days, respectively (29159,29160,29161,90502). There is insufficient reliable information available about the safety of black pepper when used orally in medicinal amounts.

CHILDREN: LIKELY SAFE
when used orally in amounts commonly found in foods (11).

CHILDREN: POSSIBLY UNSAFE
when used orally in large amounts. Fatal cases of pepper aspiration have been reported in some patients (5619,5620). There is insufficient reliable information available about the safety of topical pepper oil when used in children.

PREGNANCY: LIKELY SAFE
when used orally in amounts commonly found in foods (11).

PREGNANCY: LIKELY UNSAFE
when used orally in large amounts. Black pepper might have abortifacient effects (11,19); contraindicated. There is insufficient reliable information available about the safety of topical pepper when used during pregnancy.

LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods (11). There is insufficient reliable information available about the safety of black pepper when used in medicinal amounts during breast-feeding.

(Read more about BLACK PEPPER)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Bois de rose oil has Generally Recognized as Safe (GRAS) status in the US (4912). ...when used topically as a cosmetic ingredient; it is reported to be nontoxic (11). There is insufficient reliable information available about the safety of bois de rose oil when used orally or topically as medicine.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about BOIS DE ROSE OIL)

LIKELY SAFE ...when used orally and appropriately. Ginger has been safely used in multiple clinical trials (721,722,723,5343,7048,7084,7085,7400,7623,11346)(12472,13080,13237,13244,17369,17928,17929,89889,89890,89894)(89895,89898,89899,90102,96252,96253,96259,96260,96669) (101760,101761,101762,103359,107903).

POSSIBLY SAFE ...when used topically and appropriately, short-term (89893,89897).

CHILDREN: LIKELY SAFE
when consumed in the amounts typically found in foods.

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term. Ginger powder has been used with apparent safety at a dose of up to 750 mg daily for 4 days in girls aged 14-18 years (96255).

PREGNANCY: LIKELY SAFE
when consumed in the amounts typically found in foods. Ginger is considered a first-line nonpharmacological treatment option for nausea in pregnancy by the American College of Obstetrics and Gynecology (ACOG) (111601). However, it should not be used long-term or without medical supervision and close monitoring.

PREGNANCY: POSSIBLY SAFE
when used for medicinal purposes. Despite some early reports of adverse effects (721,7083) and one observational study suggesting that taking dried ginger and other herbal supplements during the first 20 weeks of pregnancy marginally increased the chance of stillbirth (96254), most research shows that ginger is unlikely to cause harm to the baby. The risk for major malformations in infants of parents who took ginger when pregnant does not appear to be higher than the baseline rate of 1% to 3% (721,1922,5343,11346,13071,13080,96254). Also, other research suggests that ginger intake during various trimesters does not significantly affect the risk of spontaneous abortion, congenital malformations, stillbirth, perinatal death, preterm birth, low birth weight, or low Apgar scores (18211,90103). Ginger use has been associated with an increase in non-severe vaginal bleeding, including spotting, after week 17 of pregnancy (18211).

LACTATION: LIKELY SAFE
when consumed in the amounts typically found in foods. There is insufficient reliable information available about the safety of ginger when used for medicinal purposes; avoid amounts greater than those found in foods.

(Read more about GINGER)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Juniper, juniper berry, and juniper extract have Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when used topically on limited areas of skin (12230). ...when the oil is used by inhalation and appropriately as aromatherapy (7107). There is insufficient reliable information available about the safety of juniper when used orally in doses of less than 10 grams of berries or 100 mg of oil daily, short-term. Juniper oil and berry have a long history of traditional use (12,103759).

LIKELY UNSAFE ...when used orally in excessive amounts or long-term. Use of daily doses greater than 10 grams of juniper berries (about 60 berries) or 100 mg of juniper essential oil, or prolonged oral use longer than 4 weeks, have been reported to increase the risk of severe adverse effects such as convulsions or kidney damage (8,19,103759).

PREGNANCY: UNSAFE
when used orally. Juniper can increase uterine tone, interfere with fertility and implantation, and cause abortion (4,19).

LACTATION:
Insufficient reliable information available; avoid using.

(Read more about JUNIPER)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Lavender has Generally Recognized as Safe (GRAS) status for food use in the US (4912).

POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts (9792). In clinical research, lavender essential oil, including a specific product containing lavender oil (Silexan, Dr Willmar Schwabe GmbH & Co. KG), has been used safely at doses of 80-160 mg daily for up to 10 weeks (58077,58080,58098,97257,112255,114629). Powdered dried lavender flowers 500 mg twice daily has also been used with apparent safety for up to 8 weeks (97256). ...when used topically and appropriately. Lavender oil has been used safely for up to 7 months in adults (5177,109858,109865). ...when the essential oil is inhaled as a part of aromatherapy. Clinical studies have used lavender oil aromatherapy with apparent safety for up to 12 weeks (7107,12213,16393,16394,95634,103062,103063,103065,103068,114627)(114636,114641).

CHILDREN: POSSIBLY SAFE
when the essential oil is inhaled as a part of aromatherapy. Clinical studies have used lavender oil aromatherapy with apparent safety in single doses for up to 2 hours (109868,112260).

CHILDREN: POSSIBLY UNSAFE
when applied topically in males. Anecdotal reports suggest that applying topical products containing lavender oil to prepubertal males may result in gynecomastia in some cases (15254,95643). Products with a higher concentration of lavender oil and more frequent applications might be more likely to result in gynecomastia.

PREGNANCY AND LACTATION:
Insufficient reliable evidence available. Preliminary clinical research shows that lavender essential oil can be inhaled during labor, with no apparent adverse outcomes in the infants (95633). Although this study suggests safety, high quality assessment of safety has not been conducted.

(Read more about LAVENDER)

LIKELY SAFE ...when used in amounts commonly found in foods. Marjoram and its essential oil have Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when the leaf is used orally and appropriately in tea, short-term (12,18). ...when marjoram oil is used orally and appropriately, short-term (11).

POSSIBLY UNSAFE ...when the flower, leaf, and oil are used orally, long-term. Marjoram contains arbutin, a hydroquinone glycoside (2,18). Studies in animals suggest that long-term use of hydroquinone can damage the liver and kidneys and might cause cancer (2,76395,95524). There is insufficient reliable information available about the safety of marjoram when used topically.

PREGNANCY: POSSIBLY UNSAFE
when used in medicinal amounts; marjoram has the potential for stimulating menstruation (19,95324). Avoid amounts greater than those found in foods.

LACTATION:
Insufficient reliable information available; avoid amounts greater than those found in foods.

(Read more about MARJORAM)

POSSIBLY SAFE ...when used orally and appropriately, short-term. A specific product containing Monterey pine bark extract (Enzogenol, ENZO Nutraceuticals) has been used with apparent safety at a dose of 1000 mg daily for up to 12 weeks (63614,63618,63620,105777) or 480 mg daily for up to 6 months (105778). There is insufficient reliable information available about the safety of Monterey pine when used topically.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about MONTEREY PINE)

LIKELY SAFE ...when used orally in amounts typically found in foods. Rosemary has Generally Recognized as Safe (GRAS) status in the US (4912).

POSSIBLY SAFE ...when the leaf is used orally and appropriately in medicinal amounts (18). Powdered rosemary leaf has been used with apparent safety as a single dose of up to 1.5 grams (18246,91731) or at a dose of 1-4 grams daily for up to 8 weeks (91727,98536,105327,109561). ...when the essential oil is used topically and appropriately for up to 7 months (5177,91729,109560). ...when the essential oil is used by inhalation as aromatherapy, short-term (7107,18323,105324,109559).

LIKELY UNSAFE ...when the essential oil or very large quantities of rosemary leaf are used orally. Ingestion of undiluted rosemary oil or very large quantities of rosemary leaf can cause serious adverse effects (18,515).

PREGNANCY: POSSIBLY UNSAFE
when used orally in medicinal amounts. Rosemary might have uterine and menstrual flow stimulant effects (4,12,18), and might increase metabolism of estradiol and estrone (18331); avoid using. There is insufficient reliable information available about the safety of rosemary when used topically during pregnancy.

LACTATION:
There is insufficient reliable information available about the safety of using rosemary in medicinal amounts during lactation; avoid using.

(Read more about ROSEMARY)

LIKELY SAFE ...when used orally in amounts commonly found in foods. Tangerine has Generally Recognized as Safe (GRAS) status in the US (4912). There is insufficient reliable information available about the safety of tangerine when used orally or topically as a medicine.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

(Read more about TANGERINE)

(Read more about BENZOIN)

AMOXICILLIN (Amoxil, Trimox) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the effects and side effects of amoxicillin.  Details Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin (29269). This has not been reported in humans.

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.  Details In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation (29206). This has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels (29225). Monitor blood glucose levels closely. Dose adjustments might be necessary.

ATORVASTATIN (Lipitor) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase blood levels of atorvastatin.  Details Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold (104188). This has not been reported in humans.

CARBAMAZEPINE (Tegretol) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.  Details One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects (16833). In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner (103819).

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the effects and side effects of cyclosporine.  Details In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine (29282). This has not been reported in humans.

CYTOCHROME P450 1A1 (CYP1A1) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP1A1.  Details In vitro research suggests that piperine, a constituent of black pepper, inhibits CYP1A1 (29213). This has not been reported in humans.

CYTOCHROME P450 2B1 (CYP2B1) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP2B1.  Details In vitro research suggests that piperine, a constituent of black pepper, inhibits CYP2B1 (29332). This has not been reported in humans.

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.  Details In vitro research suggests that some constituents of black pepper inhibit CYP2D6 (29207,29212,38375). This has not been reported in humans.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.  Details In vitro research shows that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4 (14375,29212). This has not been reported in humans.

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.  Details Black pepper is thought to have diuretic properties (11).

NEVIRAPINE (Viramune) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Black pepper might increase blood levels of nevirapine.  Details Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study (29209).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase levels of P-glycoprotein substrates.  Details In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein (14375,29281,29283).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black pepper might increase the sedative effects of pentobarbital.  Details Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time (29214).

PHENYTOIN (Dilantin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of phenytoin.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin (537,14442). Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin (14375). Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper (14442).

PROPRANOLOL (Inderal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of propranolol.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol (538).

RIFAMPIN (Rifadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Black pepper might increase blood levels of rifampin.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin (14375,29284).

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Black pepper might increase blood levels of theophylline.  Details Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline (538).

(Read more about BLACK PEPPER)

(Read more about BOIS DE ROSE OIL)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.  Details Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation (7622,12634,20321,20322,20323,96257). However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials (96257). Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.  Details Animal and human research suggests that ginger might increase insulin levels and/or decrease blood glucose levels (12636,20402,20403,20404,20405,89895,89896,107898).

CALCIUM CHANNEL BLOCKERS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.  Details Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects (12633). Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone (107901).

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.  Details In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time (20401).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP1A2 substrates.  Details In vitro research shows that ginger inhibits CYP1A2 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 2B6 (CYP2B6) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP2B6 substrates.  Details In vitro research shows that ginger inhibits CYP2B6 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase the levels of CYP2C9 substrates.  Details In vitro research shows that ginger inhibits CYP2C9 activity (111544). However, this interaction has not been reported in humans.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Ginger might increase or decrease the levels of CYP3A4 substrates.  Details In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity (111544,111644). Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644). Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates (111404). However, this interaction has not been reported in humans.

LOSARTAN (Cozaar) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase levels of losartan and the risk of hypotension.  Details In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan (102459). It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.

METRONIDAZOLE (Flagyl) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginger might increase levels of metronidazole.  Details In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced (20350).

NIFEDIPINE (Procardia) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.  Details Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone (20324).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.  Details In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates (111544,111644). Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration (111644).

PHENPROCOUMON (Marcoumar, others) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Ginger might increase the risk of bleeding with phenprocoumon.  Details Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea (12880).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Ginger might increase the risk of bleeding with warfarin.  Details Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation (7622,12634,20321,20322,20323). In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin (12880). In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen (20349). A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months (20348). However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176). Until more is known, monitor INRs closely in patients taking large amounts of ginger.

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ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking juniper berry with antidiabetes medications might cause additive hypoglycemia.  Details Animal research shows that juniper berry can lower blood glucose (4,10580,14907).

DIURETIC DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, juniper berry might increase the risk of adverse effects from diuretic drugs.  Details Juniper berry is thought to have mild diuretic effects (4,512).

LITHIUM Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, juniper berry might reduce lithium excretion and increase serum levels of lithium.  Details Juniper berry is thought to have mild diuretic effects (4,512).

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CNS DEPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, lavender might potentiate the therapeutic effects and adverse effects of CNS depressants.  Details Laboratory research suggests that lavender has sedative effects (7). However, clinical studies in patients taking oral lavender oil (Silexan) 160 mg for 10 weeks or taking lavender flower powder 1 gram daily for 2 months have not reported side effects of drowsiness, sedation, or sleepiness (97256,103061). There is still some concern that higher doses or different preparations of lavender might have additive effects with CNS depressant medications.

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ANTICHOLINERGIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D In vitro research suggests that marjoram extract can inhibit acetylcholinesterase activity (31438,76912). Theoretically, using marjoram in medicinal amounts along with anticholinergic drugs might decrease the effectiveness of marjoram or the anticholinergic agent.  Details Some anticholinergic drugs include atropine, benztropine (Cogentin), biperiden (Akineton), procyclidine (Kemadrin), and trihexyphenidyl (Artane).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D In vitro research suggests that marjoram extract inhibits platelet aggregation and adhesion (76932). Theoretically, marjoram might increase the risk of bleeding when used in medicinal amounts along with antiplatelet or anticoagulant drugs.  Details Some anticoagulant or antiplatelet drugs include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.

CHOLINERGIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D In vitro research suggests that marjoram extract can inhibit acetylcholinesterase activity (31438,76912). Theoretically, using marjoram in medicinal amounts along with cholinergic drugs might have additive effects and increase the risk of cholinergic side effects.  Details Cholinergic drugs include bethanechol (Urecholine), donepezil (Aricept), echothiophate (Phospholine Iodide), edrophonium (Enlon, Reversol, Tensilon), neostigmine (Prostigmin), physostigmine (Antilirium), pyridostigmine (Mestinon, Regonol), succinylcholine (Anectine, Quelicin), and tacrine (Cognex).

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, rosemary may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details In vitro and animal research suggests that rosemary inhibits platelet aggregation (18334,18335,18336,18337).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, taking rosemary with antidiabetes drugs might increase the risk of hypoglycemia.  Details Animal research shows that rosemary extract can decrease blood glucose levels in diabetic models (71821,71923). However, research in humans is conflicting. Although rosemary powder decreased blood glucose levels in healthy adults (105327), no change in blood glucose levels was seen in adults with type 2 diabetes, most of whom were taking antidiabetes drugs (105323,105327).

ASPIRIN Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, rosemary might have additive effects with salicylate-containing drugs such as aspirin.  Details Rosemary is reported to contain salicylates (18330).

CHOLINE MAGNESIUM TRISALICYLATE (Trilisate) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, rosemary might have additive effects with salicylate-containing drugs such as choline magnesium trisalicylate.  Details Rosemary is reported to contain salicylate (18330).

CYTOCHROME P450 1A1 (CYP1A1) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, rosemary might decrease the levels and clinical effects of CYP1A1 substrates.  Details In vitro research shows that rosemary induces CYP1A1 enzymes (18332,18333). This effect has not been reported in humans.

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, rosemary might decrease the levels and clinical effects of CYP1A2 substrates.  Details In vitro research shows that rosemary induces CYP1A2 enzymes (18332,18333). This effect has not been reported in humans.

SALSALATE (Disalcid) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, rosemary might have additive effects with salicylate-containing drugs such as salsalate.  Details Rosemary is reported to contain salicylate (18330).

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CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = B In vitro, tangeretin, a constituent of tangerine, induces a 52% increase in the metabolism of midazolam by cytochrome P450 3A4 (CYP3A4) (28609). This suggests that tangeretin may stimulate CYP3A4 activity. However, in humans, drinking tangerine juice 200 mL slightly delayed the absorption, but did not affect the metabolism, of midazolam, a CYP3A4 substrate (28609). Theoretically, tangerine juice might increase CYP3A4 activity and decrease levels of drugs metabolized by this enzyme. However, this effect is unlikely.  Details Some drugs metabolized by CYP3A4 include amitriptyline (Elavil), amiodarone (Cordarone), citalopram (Celexa), felodipine (Plendil), lansoprazole (Prevacid), ondansetron (Zofran), prednisone (Deltasone, Orasone), sertraline (Zoloft), sibutramine (Meridia), and many others.

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General ...Orally, compound benzoin tincture has been reported to cause gastritis and gastrointestinal hemorrhage (6002). Topically, benzoin and compound benzoin tincture can cause contact dermatitis and other skin reactions (11,12,103827).

Dermatologic ...Benzoin can cause urticaria and skin discoloration (6002). Allergic contact dermatitis to benzoin and compound benzoin tincture has been reported and confirmed by patch testing (11,12,103827). In clinical research, the incidence of localized contact dermatitis with compound benzoin tincture is 8% to 9%, with a lower incidence of generalized allergic dermatitis (103827).

Gastrointestinal ...A case report describes gastritis and gastrointestinal hemorrhage in a young man who took compound benzoin tincture 2 teaspoons twice daily for 10 days orally, instead of by inhalation (6002).

Pulmonary/Respiratory ...Inhalation of compound benzoin tincture can cause asthmatic symptoms (6002).

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General ...Orally, black pepper seems to be well tolerated when used in the amounts found in food or when taken as a medicine as a single dose. Topically and as aromatherapy, black pepper oil seems to be well tolerated.
Most Common Adverse Effects:
Orally: Burning aftertaste, dyspepsia, and reduced taste perception.
Inhalation: Cough.
Serious Adverse Effects (Rare):
Orally: Allergic reaction in sensitive individuals.

Gastrointestinal ...Orally, black pepper can cause a burning aftertaste (5619) and dyspepsia (38061). Single and repeated application of piperine, the active constituent in black pepper, to the tongue and oral cavity can decrease taste perception (29267). By intragastric route, black pepper 1.5 grams has been reported to cause gastrointestinal microbleeds (29164). It is not clear if such an effect would occur with oral administration.

Immunologic ...In one case report, a 17-month-old male developed hives, red eyes, facial swelling, and a severe cough following consumption of a sauce containing multiple ingredients. Allergen skin tests were positive to both black pepper and cayenne, which were found in the sauce (93947).

Ocular/Otic ...Topically, ground black pepper can cause redness of the eyes and swelling of the eyelids (5619).

Pulmonary/Respiratory ...When inhaled through the nose as an olfactory stimulant, black pepper oil has been reported to cause cough in one clinical trial (29162).

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General ...Bois de rose oil is well tolerated when used orally in amounts commonly found in foods or when used topically as an ingredient in cosmetic products (11,4912). When used as medicine, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.

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General ...Orally, ginger is generally well tolerated. However, higher doses of 5 grams per day increase the risk of side effects and reduce tolerability. Topically, ginger seems to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal discomfort, burping, diarrhea, heartburn, and a pepper-like irritant effect in the mouth and throat. However, some of these mild symptoms may be reduced by ingesting encapsulated ginger in place of powdered ginger.
Topically: Dermatitis in sensitive individuals.

Cardiovascular ...Orally, use of ginger resulted in mild arrhythmia in one patient in a clinical trial (16306).

Dermatologic ...Orally, ginger can cause hives (17933), as well as bruising and flushing (20316) or rash (20316).
Topically, ginger can cause dermatitis in sensitive individuals (12635,46902).

Gastrointestinal ...Orally, common side effects of ginger include nausea (17933,22602,89898,101761), belching (10380,103359), dry mouth (103359), dry retching (10380), vomiting (10380), burning sensation (10380), oral numbness (22602), abdominal discomfort (5343,89898,96253), heartburn (5343,7624,12472,16306,20316,51845,89894,89895,89898,89899)(101760,101761,101762,111543), diarrhea (5343,101760), constipation (89898,101760,101761), or a transient burning or "chilly hot" sensation of the tongue and throat (52076). Orally, Number Ten, a specific product composed of rhubarb, ginger, astragalus, red sage, and turmeric, can increase the incidence of loose stools (20346).
Four cases of small bowel obstruction due to ginger bolus have been reported following the ingestion of raw ginger without sufficient mastication (chewing). In each case, the bolus was removed by enterotomy. Ginger is composed of cellulose and therefore is resistant to digestion. It can absorb water, which may cause it to swell and become lodged in narrow areas of the digestive tract (52115).

Genitourinary ...In one clinical trial, some patients reported increased menstrual bleeding while taking a specific ginger extract (Zintoma, Goldaru) 250 mg four times daily orally for 3 days (17931). An "intense" urge to urinate after 30 minutes was reported in two of eight patients given 0.5-1 gram of ginger (7624). However, this effect has not been corroborated elsewhere. Dysuria, flank pain, perineal pain, and urinary stream interruption have been reported in a 43-year-old male who drank ginger tea, containing 2-3 teaspoons of dry ginger, daily over 15 years. The adverse effects persisted for 4 years and were not associated with increases in urinary frequency or urgency. Upon discontinuing ginger, the patient's symptoms began to improve within one week and completely resolved after eight weeks, with no relapses six months later (107902).

Immunologic ...In one case report, a 59-year-old Japanese female with multiple allergic sensitivities developed pruritus and then anaphylactic shock after taking an oral ginger-containing herbal supplement for motion sickness (Keimei Gashinsan, Keimeido). The patient had used this supplement previously for over 20 years with no allergic reaction. The authors theorized the development of a cross-reactivity to ginger after the use of an oral supplement containing zedoary and turmeric, which are also in the Zingiberaceae family (102463).

Neurologic/CNS ...Orally, ginger may cause sedation, drowsiness, or dizziness (16306,17933,51845).

(Read more about GINGER)

General ...Orally and topically, juniper seems to be generally well tolerated when used short-term in low doses. However, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Topically: Allergies, skin irritation.

Dermatologic ...Topically, juniper can cause skin irritation. Signs of topical poisoning include burning, erythema, inflammation with blisters, and edema (4). Repeated exposure to the juniper pollen can cause occupational allergies that affect the skin (6). In a case report, a 62-year-old woman developed burn-like blistering lesions after carrying juniper in close contact to her skin. Concurrent sun exposure was thought to worsen the skin irritation caused by juniper (103756).

Genitourinary ...Orally, large amounts of the juniper berry can cause purplish urine (4).

Pulmonary/Respiratory ...Repeated exposure to the juniper pollen can cause occupational allergies that affect the respiratory tract (6).

(Read more about JUNIPER)

General ...Orally, lavender is well tolerated in food amounts and seems to be well tolerated in larger amounts. Topically, lavender oil seems to be well tolerated.
Most Common Adverse Effects:
Orally: Breath odor, constipation, diarrhea, dyspepsia, eructation, headache, and nausea.
Topically: Allergic contact dermatitis (with lavender oil).
Serious Adverse Effects (Rare):
Topically: Cases of gynecomastia have been reported in prepubertal males using lavender oil.

Cardiovascular ...Orally, a specific lavender oil ingredient (Silexan) has been associated with palpitations (103061).

Endocrine ...Topical products containing lavender oil alone, including a product referred to as agua de violetas, or in combination with tea tree oil have been linked to at least six cases of gynecomastia when used in prepubertal males. In each case, gynecomastia resolved when the lavender oil products were discontinued. It is thought that the estrogenic and antiandrogenic activity of lavender oil and tea tree oil resulted in gynecomastia in these cases (15254,95643).

Gastrointestinal ...Orally, lavender oil, including a specific lavender oil ingredient KG), may cause gastrointestinal disturbance, including dyspepsia, diarrhea, breath odor, eructation, and nausea (58077,58080,58098,93004,103061,114631). Tincture of lavender has been linked to cases of constipation and increased appetite; however, it is unknown if this occurred at a greater rate than with placebo (9792).

Immunologic ...Topically, use of lavender oil, such as in personal care products, might cause allergic contact dermatitis in some patients (6,101728). There have been numerous case reports of allergic contact dermatitis and eczema linked to lavender oil exposure from shampoos, lotions, fragrances, or direct application of oil to pillows (10031,58043,58109,58120,101728,112253). In one case series, only 4 out of 15 cases of allergic contact dermatitis due to lavender had positive patch tests for lavender. Oxidation products of lavender essential oils such as linalool, linalyl acetate, limonene, cineol, geraniol, eugenol, and isoeugenol may be more allergenic than un-oxidized lavender essential oil, which may result in a false negative patch test (112253). Orally, taking lavender was associated with itching and rash in one clinical study participant (114634).

Neurologic/CNS ...Orally, lavender flower powder, tincture of lavender containing 50% alcohol, and a specific lavender oil ingredient (Silexan) have been linked to headache (9792,103061,109860). Headache has also been reported rarely following lavender oil aromatherapy (109860).

Pulmonary/Respiratory ...In one case report, a 34-year-old Japanese female presented with complaints of dyspnea, cough, and fever 2 weeks after initiating lavender essential oil therapy via humidifier. The patient had an oxygen saturation of 88% and was diagnosed with acute eosinophilic pneumonia. Symptoms improved after a course of corticosteroids and discontinuation of aromatherapy (109979).

Renal ...In one case report, a 24-year-old male presented with shortness of breath, weakness, nausea, and decreased urine output following the intake of Spanish lavender tea twice daily for 5 days. After presenting to the hospital, the patient was diagnosed with acute kidney failure secondary to acute interstitial nephritis likely due to lavender consumption (112259).

(Read more about LAVENDER)

General ...Orally, marjoram and its essential oil are well tolerated in amounts commonly found in foods (4912). Marjoram leaf and marjoram oil seem to be well tolerated when used appropriately for medicinal purposes (2,11,12,18). However, marjoram flower, leaf, and oil should not be used long-term due to the arbutin content (2,76395,95524).
Topically, there are rare reports of allergic skin reactions with marjoram use (33865,58049).

Immunologic ...Possible allergic contact dermatitis in children with pre-existing childhood atopic eczema was observed in a randomized clinical trial employing extended use of essential oils, including sweet marjoram essential oil (58049). A case report describes a 38-year old woman who had an exacerbation of perioral dermatitis after eating food seasoned with marjoram. The dermatitis resolved within 3 weeks on a marjoram-free diet, but reappeared when she was rechallenged with marjoram (33865).

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General ...Orally, Monterey pine seems to be well tolerated. Topically, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.

Dermatologic ...Contact dermatitis from Monterey pine sawdust has been reported (63615).

Immunologic ...Monterey pine pollen may cause seasonal rhinoconjunctivitis (63612).

(Read more about MONTEREY PINE)

General ...Orally, rosemary seems to be well tolerated when used in appropriate medicinal amounts. Undiluted rosemary oil or very large quantities of rosemary leaf should not be consumed. Topically and as aromatherapy, rosemary seems to be well tolerated.

Dermatologic ...Topically, rosemary use can lead to photosensitivity, erythema, dermatitis, and cheilitis in hypersensitive individuals (4,6).

Immunologic ...Topically, allergic reactions can occur. When used in the mouth, lip and gum edema have occurred (101173). When used on the skin, allergic contact dermatitis has occurred, likely due to the constituent carnosol (71715,71924,71926).
Rosemary might also cause occupational asthma. A case of occupational asthma caused by several aromatic herbs including thyme, rosemary, bay leaf, and garlic has been reported. The diagnosis was confirmed by inhalation challenges. Although all of the herbs caused immediate skin reactivity, a radioallergosorbent test (RAST) showed that garlic was the most potent allergen by weight, with rosemary and the other herbs showing less reactivity (783).

Neurologic/CNS ...Orally, the undiluted oil, as well as the camphor constituent of rosemary, might cause seizures (4,5,6,12868).

(Read more about ROSEMARY)

General ...Orally, very few adverse effects have been reported with the medicinal use of tangerine. However, a thorough evaluation of safety outcomes has not been conducted.
Topically, contact dermatitis has been associated with tangerine essential oil (28610).

Dermatologic ...According to one case report, the essential oil of tangerine in a fragrance has been associated with contact dermatitis (28610).

Gastrointestinal ...In a case report, a 5 year-old patient had a phytobezoar that included tangerine residues (28611). In another case report, orange and tangerine caused obstruction of the small intestine (28612).

(Read more about TANGERINE)