Lavender Calm by Nature's Life

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)

EFFECTIVE

• Bowel preparation. Various magnesium salts are used for cleansing the bowel prior to procedures such as colonoscopy. Details: Various magnesium salts, including citrate, hydroxide, oxide, and sulfate, are ingredients in bowel preparation products available over-the-counter or by prescription only.
• Constipation. Magnesium salts are effective when used short-term orally to treat constipation and chronic idiopathic constipation (CIC). Details: Magnesium citrate, hydroxide, oxide, and sulfate salts are commonly used as laxatives. Magnesium citrate 11.3-17.45 grams has been used; magnesium hydroxide 2.4-4.8 grams, as 30-60 mL of milk of magnesia, has also been used (113483,113484). Magnesium sulfate, also known as Epsom salt, which seems to have the most potent effect, has been used as 10-30 grams (6430,113485). Magnesium salts should only be used for occasional treatment of constipation, and doses should be taken with a full 8-ounce glass of water. Magnesium oxide seems to be beneficial in adults with CIC when taken short-term. Clinical guidelines published by the American Gastroenterology Association and American College of Gastroenterology in 2023 give a conditional recommendation suggesting the use of magnesium oxide over managing CIC without magnesium oxide based on low-quality studies conducted over 4 weeks. The recommended starting dose is 400-500 mg daily with dose titration per symptom response and side effects (112859). A small clinical study in patients with CIC who are not taking chronic medications shows that taking magnesium oxide 1.5 grams in three divided doses daily for 28 days increases spontaneous bowel movements when compared with placebo (104397). It is unknown if magnesium is beneficial for CIC when used long-term.
• Dyspepsia. Magnesium salts are effective when used orally as antacids. Details: Magnesium carbonate, hydroxide, oxide, or trisilicate salts are used orally as antacids to reduce symptoms of gastric hyperacidity or gastroesophageal reflux. Magnesium hydroxide has the fastest onset of action. The onset for magnesium carbonate is slower due to its crystal structure. Magnesium trisilicate has the slowest onset and longest duration of action due to poor solubility (6844). Doses used include magnesium hydroxide 400-1200 mg (5-15 mL of milk of magnesia) up to four times daily, or magnesium oxide 800 mg daily (15).
• Eclampsia. Magnesium sulfate is considered the drug of choice for control of seizures. Details: Intravenous (IV) and/or intramuscular (IM) magnesium sulfate is considered the agent of choice for seizure prophylaxis during eclampsia by the American College of Obstetricians and Gynecologists (ACOG) (15,12591,12592,61012,61184). Typical doses include 4-6 grams of magnesium sulfate by IV infusion in 250 mL of dextrose 5% or normal saline solution, followed by 4-5 grams of magnesium sulfate IM every 4 hours, or 1-3 grams per hour by continuous IV infusion. Doses should be adjusted according to serum levels and urinary excretion, and should not exceed 30-40 grams of magnesium sulfate daily (15,12591). Meta-analyses of clinical research show that treatment with IV or IM magnesium reduces the risk of seizure recurrence by 33% to 69% when compared with phenytoin, and by 47% to 60% when compared with diazepam (19960,60818,60954,60964,61105). One preliminary clinical study shows that lower doses of IV magnesium sulfate (9 grams loading dose and maintenance of 2.5 grams every 4 hours for 24 hours) are as effective as higher doses (14 grams loading dose and maintenance of 5 grams every 4 hours for 24 hours) for reducing the recurrence of eclamptic seizures (89383). It is generally recommended that treatment be continued for at least 24 hours after the last seizure (15). Oral magnesium has not been evaluated for eclampsia.
• Hypomagnesemia. Hypomagnesemia can be effectively treated with oral or parenteral magnesium. Details: Taking magnesium orally or parenterally is helpful for treating and preventing hypomagnesemia associated with alcoholism, cirrhosis of the liver, congestive heart failure (CHF), severe or prolonged diarrhea or vomiting, kidney dysfunction, inflammatory bowel disease (IBD), pancreatitis, malabsorption syndromes, and other conditions (6280,6281,8088,8089). The dose and salt of magnesium for oral replacement therapy should be chosen carefully to avoid causing diarrhea. The gluconate and chloride salts cause less diarrhea, while the oxide salt is more likely to cause diarrhea and should be avoided. Magnesium chloride should also be avoided due to poor solubility which decreases absorption (6430,8099,10664). Orally, magnesium sulfate 3 grams every 6 hours for four doses has been used for hypomagnesemia (15). Parenteral magnesium doses must be individualized according to serum magnesium levels, but a typical starting dose for mild deficiency is 1 gram of magnesium sulfate intramuscularly (IM) every 6 hours for 4 doses (15). For more severe deficiency, 5 grams of magnesium sulfate may be given as an intravenous (IV) infusion in 1 liter of dextrose 5% or normal saline solution over 3 hours (15).
• Pre-eclampsia. Magnesium sulfate is considered the drug of choice for seizure prophylaxis in patients with pre-eclampsia. Details: Intravenous (IV) and/or intramuscular (IM) magnesium sulfate is considered the agent of choice for seizure prophylaxis during pre-eclampsia by the American College of Obstetricians and Gynecologists (ACOG) (12591,12592,61012,61184). Some meta-analyses show that IV administration of magnesium sulfate reduces the risk of eclampsia when compared with placebo, phenytoin, or diazepam in patients with pre-eclampsia (19960,60818,60960,60979). A typical initial dose is 4-5 grams of magnesium sulfate by IV infusion in 250 mL of dextrose 5% or normal saline solution, followed by 4-5 grams of magnesium sulfate IM every 4 hours, or 1-3 grams of magnesium sulfate per hour by continuous IV infusion. Doses should be adjusted according to serum levels and urinary excretion, and should not exceed 30-40 grams of magnesium sulfate daily (15,12591). The optimal duration of prophylaxis has not been determined. A meta-analysis suggests that using a shorter duration of 12 hours or less is not associated with an increase in risk of eclamptic seizures when compared with regimens of 24 hours or longer (108732). However, studies are likely underpowered due to the low incidence of eclampsia. Oral magnesium has been evaluated for the prevention of pre-eclampsia in healthy adults, but taking magnesium citrate 300 mg daily, starting at 12-20 weeks' gestation and continuing until delivery, does not reduce the incidence of pre-eclampsia when compared with placebo (103724).

LIKELY EFFECTIVE

• Cerebral palsy. Most evidence shows that antenatal magnesium reduces the risk of cerebral palsy in preterm infants, although there are some inconsistent results. Details: Most clinical studies and meta-analyses show that antenatal magnesium sulfate reduces the risk of cerebral palsy by about 32% and the risk of motor dysfunction by about 45% in preterm infants (60915,60927,60931,61001,97485,103734,103754,114675,114681). The lowest effective dose of magnesium sulfate seems to be 4 grams intravenously, with or without a maintenance dose of 1 gram/hour until birth or for 24 hours. In obese females, a higher dose, based on body weight, may be needed (97485,97495,103734,103754). However, some studies have inconsistent results (8093,19998,98293,98295,112784). Giving females at risk of imminent preterm birth (prior to 32 weeks), intravenous magnesium sulfate 4.5 grams over 20 minutes followed by 1 gram per hour until birth or for 24 hours, in addition to a standard treatment protocol, does not reduce the incidence of cerebral palsy (112784). Oral magnesium has not been evaluated for this purpose.
• Seizures. Intravenous magnesium sulfate is used for treating seizures of various etiologies. Details: Intravenous magnesium sulfate may be useful for controlling seizures associated with epilepsy, glomerulonephritis, hypothyroidism, and acute nephritis in children (15). Oral magnesium has not been evaluated for this purpose.
• Torsades de pointes. Intravenous magnesium sulfate is the first-line treatment for torsades de pointes after measures to correct precipitating factors have been unsuccessful. Details: Intravenous magnesium sulfate has been used successfully to treat the life-threatening ventricular tachycardia, torsades de pointes (15,6844). The Advanced Cardiac Life Support (ACLS) guidelines of the American Heart Association recommend a dose of 1 to 2 grams diluted in 50-100 mL Dextrose 5% solution given IV over 5-60 minutes, followed by a continuous IV infusion of 0.5-1 gram/hour.

POSSIBLY EFFECTIVE

• Arrhythmia. Magnesium sulfate is effective for the specific type of ventricular tachycardia known as torsades de pointes, and seems to be helpful for treating other types of arrhythmias. Evidence for the role of oral or intravenous magnesium in preventing postoperative arrhythmias is conflicting. Details: Administering magnesium intravenously or orally may be helpful for treating atrial and ventricular tachycardia and fibrillation, and supraventricular tachycardia (9497,13352,13354,13355,13356,60804,60829,60877,61113,111696). Arrhythmias associated with congestive heart failure have been treated with magnesium sulfate 8 grams infused over 12 hours (9497). For rate control in atrial fibrillation, magnesium sulfate 2.5 grams IV over 20 minutes, followed by 2.5 grams IV over 2 hours has been used (13356). For paroxysmal supraventricular tachycardia, single doses of 1-4 grams of magnesium chloride have been used (13352). For atrial tachycardia, 2 grams of magnesium sulfate in 10 mL of dextrose 5% solution has been given IV over 1-10 minutes, followed by 5-10 grams of magnesium sulfate in 250-500 mL dextrose 5% solution as an IV infusion over 5 hours (13354,13355). Research on the effects of intravenous magnesium for preventing arrhythmias after cardiac surgery is conflicting. Some meta-analyses show that intravenous magnesium reduces the risk of atrial fibrillation, ventricular arrhythmias, or supraventricular arrhythmias following cardiac surgery by 23% to 48% when compared with placebo (60814,60826,60828,60838,61008,61033,61181,97487,97490). Doses of magnesium sulfate used include 30 mg/kg in 500 mL normal saline (97490), or 80-100 mg/kg added to the cardioplegia solution (97487). Also, one small study in adults after CABG surgery suggests that taking magnesium hydroxide 1600 mg orally reduces arrhythmia as effectively as receiving magnesium sulfate 2000 mg intravenously (99315). However, other meta-analyses that only include higher-quality trials show that magnesium supplementation does not reduce the risk of ventricular or supraventricular arrhythmias following cardiac surgery (61010,61024,61031,105081). A meta-analysis of clinical trials of intravenous magnesium for prevention of new-onset atrial fibrillation after non-cardiac surgeries shows that it does not reduce the incidence significantly when compared with placebo (112778). However, there was a high risk of bias in the analysis, and variability in types of surgery, and the salt and dose of magnesium used.
• Asthma. Parenteral magnesium sulfate can help to reverse severe acute asthma attacks and reduce the need for hospital admission. It is unclear if nebulized magnesium is beneficial for acute asthma attacks. However, oral magnesium does not seem to be beneficial. Details: Overall, a single dose of intravenous magnesium seems to improve pulmonary function in acute asthma exacerbation and reduce the risk of hospitalization, particularly in patients with severe asthma, and those who have failed initial treatment with nebulized albuterol and intravenous corticosteroids (60888,90023,96483,104398,107365). The typical dose used for adults is 2 grams of magnesium sulfate infused over 20 minutes (15). For children, 25-75 mg/kg, to a maximum of 2 grams, infused over 20-30 minutes has been used (15,96483,107365). However, a post-hoc analysis of one large clinical trial (104400) designed to assess nebulized magnesium in children with acute asthma has found that adding IV magnesium to nebulized magnesium is associated with greater odds of hospitalization when compared with no IV magnesium (105919). This post-hoc analysis did not differentiate between precautionary and necessary hospitalizations. Although some clinical research and a meta-analysis in patients with acute asthma exacerbation show that nebulized magnesium in combination with standard treatment improves airway function, respiratory rate, and clinical asthma severity when compared with standard treatment alone, it is unclear whether these findings are clinically relevant (90016,113466). Most evidence, including larger clinical trials and meta-analyses, has not shown benefit of adjunct nebulized magnesium for acute asthma in adults or children (60888,90002,96484,104400,105920,113466,114674). Oral magnesium also does not seem to be beneficial. A meta-analysis of small clinical trials in children and adults with asthma shows that taking magnesium supplements orally does not improve lung function or reduce bronchodilator use when compared with control (104404).
• Colorectal cancer. Increasing dietary magnesium intake seems to lower the risk of colon cancer but not rectal cancer. Details: Epidemiological research shows that increased dietary magnesium intake is associated with a reduced risk of colon cancer, but the risk of rectal cancer is not affected (89387,90017,90027,101355).
• Diabetes. Low dietary magnesium may increase the risk of developing type 2 diabetes, but evidence on the use of supplements for treating type 2 diabetes is conflicting. Details: Higher dietary magnesium intake is associated with lower fasting insulin concentrations and a reduced risk of developing type 2 diabetes in adults and obese children (13369,15548,96473,97486,98294,103736,105918,106920). In people with existing type 2 diabetes, hypomagnesemia is found in 25% to 38% of patients, especially in those with poorly controlled diabetes (1172). Population research in adults with type 2 diabetes also shows that a dietary magnesium intake of less than 250 mg daily is associated with a 56% higher risk of mortality. Preliminary subgroup analyses suggest that the risk of mortality is higher in those with glycated hemoglobin (HbA1C) levels above 7% (110051). A meta-analysis of small, heterogeneous clinical studies in adults with type 2 diabetes suggests that magnesium may modestly reduce HbA1C in patients with hypomagnesemia, but not in patients with normal magnesium levels, when compared with control (105075). Individual clinical studies using magnesium supplements in patients with type 2 diabetes or insulin resistance have shown mixed results. Some research suggests magnesium supplements can decrease fasting blood glucose and improve insulin sensitivity, as well as reduce the risk of developing diabetes in high-risk patients (10664,12582,13376,60854,99313,106920), but other research shows no effect (1171,1172,13379,13380,112780). Discrepancies in these findings might reflect differences in magnesium salts and doses used, or differences in baseline magnesium status in study subjects.
• Hypercholesterolemia. Magnesium may help improve lipid levels by a small amount in people with this condition. Details: There is some evidence that taking magnesium oxide 1 gram orally daily for 6 weeks can produce small decreases in low-density lipoprotein (LDL) and total cholesterol levels, and small increases in high-density lipoprotein (HDL) levels in patients with hypercholesterolemia. However, magnesium does not seem to improve lipoprotein (a) levels (1193). Magnesium may also lower triglycerides in people with hypertriglyceridemia (97494).
• Metabolic syndrome. Low dietary and serum levels of magnesium seem to be associated with the development of metabolic syndrome. Details: Higher magnesium intake from diet and supplements is associated with a 27% lower risk of developing metabolic syndrome in healthy females (13371) and a 31% lower risk in healthy young adults (14304). Additional epidemiological research suggests that people with low serum magnesium levels are 6-7 times more likely to have metabolic syndrome than people with normal magnesium levels (13372). In a population analysis of over 6000 individuals without metabolic syndrome at baseline, the risk of developing this condition over a 6-year follow-up period was reduced by 16% in the highest quintile of dietary magnesium intake (median intake 371 mg daily) when compared with the lowest quintile (median intake 203 mg daily). Some, but not all, research suggests that the hazard ratio for metabolic syndrome in relation to magnesium intake may be U-shaped, with higher risk at intakes below about 150 mg daily and above 600 mg daily (108963). A combination of magnesium 20 mEq daily and potassium 40 mEq daily (magnesium potassium citrate) taken orally for 16 weeks reverses metabolic side effects of chlorthalidone, such as increased fasting plasma glucose and hypokalemia, more effectively than potassium chloride 40 mEq daily alone (112932).
• Osteoporosis. Increased dietary and supplemental magnesium intake seems to increase bone mineral density and decrease bone loss in postmenopausal patients. Details: Preliminary clinical research shows that taking magnesium hydroxide orally, 300-1800 mg daily for 6 months, then 600 mg daily for 18 months, or magnesium citrate orally 1830 mg daily for 30 days, might reduce bone loss and bone turnover in postmenopausal patients with osteoporosis (9104,60928). Some epidemiological research also suggests that magnesium intake is related to increased bone mineral density (12501,12502,12503,12504,90014), although not all studies have found an association (12505,98286).
• Postoperative pain. Injectable magnesium has been used with promising results for reducing pain and the need for other analgesics postoperatively. Details: A meta-analysis of 25 clinical trials shows that intravenous (IV) magnesium sulfate, 5-50 mg/kg bolus followed by a continuous infusion of 6 mg/kg or 500 mg hourly during surgery, seems to reduce the 24-hour postoperative use of IV morphine by 24% when compared with placebo (19968). Adding IV magnesium sulfate 3.7-5.5 grams to patient-controlled analgesia for 24 hours after surgery has also been used (19968). Additionally, meta-analyses support that adjunctive IV or intrathecal administration of magnesium reduces post-operative pain scores, improves pain relief and sensory nerve block, and decreases the need for other analgesics, when compared with control (89390,90012,90015,98287,103728,114676,114677,114678). However, some data are conflicting. In a meta-analysis of 7 trials, IV magnesium was not associated with lower pain scores over the first 48 hours postoperatively. The reasons for these discrepant findings are unclear but may be explained by differences in magnesium regimens, anesthesia protocols, and surgical populations studied. Additionally, IV magnesium appears to be less effective than dexmedetomidine (105082). Two moderate-sized clinical studies in patients undergoing total knee arthroplasty in China show that adding magnesium sulfate 2.5 mg/mL to the periarticular infiltration analgesia (PIA) cocktail or administering IV magnesium sulfate 40 mg/kg before anesthesia induction then as a 15 mg/kg infusion during surgery reduces pain scores, increases comfort levels, limits and delays the use of postoperative opioids, prolongs analgesia, and reduces markers of inflammation when compared with the usual PIA cocktail or control (111181,113677). Administering magnesium intravenously also seems to be helpful for pain control after hysterectomy. A 3-gram IV bolus of magnesium sulfate followed by an infusion of 0.5 grams per hour for 20 hours has been used. Lower doses were not effective (6848). In males undergoing laparoscopic radical resection for gastrointestinal cancer, administering IV magnesium intraoperatively, as a loading dose of 40 mg/kg followed by 15 mg/kg/hour through the end of surgery, reduces postoperative catheter-related bladder discomfort and analgesic requirements, when compared with placebo (112783). However, IV magnesium might not alleviate postoperative pain in children. Two small clinical studies show that administering a magnesium IV infusion does not reduce pain when compared with saline in children after tonsillectomy or after elective strabismus surgery (98282,105077).
• Premenstrual syndrome (PMS). Taking magnesium orally seems to relieve symptoms of PMS. Details: There is some evidence that magnesium supplementation can improve symptoms, including mood changes and fluid retention, in some patients with PMS (1187,1188,6847). Doses used include magnesium oxide 333 mg daily for 2 menstrual cycles, or magnesium pyrrolidone carboxylic acid equivalent to 360 mg elemental magnesium three times daily, from the 15th day of the menstrual cycle until onset of menstrual flow (1187,1188). Taking magnesium orally in a dose of 360 mg (elemental magnesium) three times daily for 2 months seems to prevent premenstrual migraine (1186,6847). A combination of magnesium 200 mg daily plus vitamin B6 50 mg daily seems to reduce anxiety-related premenstrual symptoms, including nervous tension, mood swings, irritability, and anxiety, when compared with placebo (8555).
• Vasospastic angina. Intravenous magnesium seems to prevent coronary spasm in patients with this condition. Details: Clinical research shows that administration of intravenous magnesium sulfate 65 mg/kg infused over 20 minutes dilates coronary arteries and suppresses acetylcholine-induced coronary spasms when compared with infusion of a dextrose solution in patients with vasospastic angina (8091).

POSSIBLY INEFFECTIVE

• Altitude sickness. Taking magnesium citrate orally does not seem to reduce acute altitude sickness risk. Details: Clinical research shows that taking magnesium citrate 1200 mg daily orally in three divided doses, beginning 3 days prior to mountain ascent and continuing until mountain descent, does not reduce the risk of acute altitude sickness when compared with placebo (60801).
• Athletic performance. Taking magnesium orally does not seem to improve energy or endurance during athletic activity. Details: Most evidence suggests that taking magnesium orally doesn't increase energy and endurance during athletic activity. Magnesium oxide, aspartate, and orotate salts do not seem to improve exercise performance when used alone or in combination with potassium, vitamin B6, or zinc (2825,2826,2828,2829,2830,60751,113655).
• Bronchiolitis. Intravenous or nebulized magnesium is not beneficial in infants with this condition. Details: Clinical research shows that administering a single IV dose of magnesium sulfate 100 mg/kg to infants with acute bronchiolitis does not improve, and may actually worsen, symptoms when compared with placebo (97482). A clinical study in infants with moderate to severe bronchiolitis shows that adding nebulized magnesium sulfate 40 mg/kg to nebulized epinephrine does not reduce hospital stay or the need for ventilator or oxygen support when compared with epinephrine alone (99317). Oral magnesium has not been evaluated for this use.
• Chemotherapy-induced peripheral neuropathy. Research on the effects of intravenous infusions of magnesium and calcium for preventing oxaliplatin neurotoxicity are inconsistent, but higher quality studies seem to show no benefit. Details: Pooled analyses of cohort studies and clinical trials show that calcium and magnesium infusions can decrease the incidence of severe oxaliplatin-induced neurotoxicity (90028,90029,90031). However, when only clinical trials are considered, the infusions do not appear to be helpful (90005,90029,90031,96474,96479).
• Complex regional pain syndrome. Intravenous magnesium is not beneficial in complex regional pain syndrome type 1. Details: Clinical research shows that receiving magnesium sulfate 70 mg/kg intravenously at the rate of 25 mL/hour for 4 hours each day for 5 days does not improve pain or level of impairment when compared with placebo in patients with chronic complex regional pain syndrome type 1 (89395).
• Emergence delirium. The majority of small clinical studies in adults and children undergoing various surgeries suggest that intravenous (IV) magnesium doesn't reduce the risk of emergence delirium. However, most clinical studies in adults suggest that IV magnesium reduces emergence agitation. Details: A small clinical study in adults undergoing surgery for endovascular aortic aneurysm repair shows that administering IV magnesium 30 mg/kg as a loading dose, followed by a 10 mg/kg/hour infusion for the duration of surgery, does not improve agitation or delirium scores when compared with administering saline (111182). Similarly, a small clinical study in children ages 2-5 years undergoing elective strabismus surgery shows that administering IV magnesium during anesthesia does not seem to prevent the occurrence of emergence delirium when compared with administering saline (105077). In a meta-analysis of 8 clinical trials in children aged 2-16 years undergoing general anesthesia for oral or ophthalmic surgery, giving IV magnesium as a 30 mg/kg loading dose followed by a 10 mg/kg/hour infusion, or as a single dose of 15-30 mg/kg, does not reduce emergence delirium scores, and may actually prolong emergence times (108729). However, there is some conflicting evidence. In patients undergoing radical mastectomy, giving intraoperative magnesium sulfate 30mg/kg over 1 hour, followed by 10 mg/kg/hour until the end of surgery, reduces emergence agitation (odds ratio 0.26) when compared with placebo (112781).
• Menopausal symptoms. Oral magnesium oxide does not seem to be beneficial for menopausal hot flashes. Details: A small, low quality study in postmenopausal patients with a history of breast cancer shows that taking magnesium oxide 400-800 mg orally daily reduces hot flashes when compared with baseline (102454). However, a larger, higher quality clinical study using magnesium oxide 800-1200 mg daily did not show any benefit when compared with placebo (98290).
• Muscle cramps. Oral magnesium does not seem to improve muscle cramp frequency or intensity. Details: Meta-analyses of small clinical trials show that magnesium supplementation for 3-6 weeks does not decrease the frequency or intensity of skeletal muscle cramps, whether the cramps are idiopathic or due to liver cirrhosis or pregnancy, when compared with placebo (90022,104395).
• Sickle cell disease. Intravenous magnesium does not add any benefit to standard therapy for sickle cell disease in children. Details: Clinical research shows that giving magnesium sulfate 40-100 mg/kg (maximum of 2 grams per dose) intravenously every hour for 6-8 doses as an adjunct to standard therapy does not decrease hospital stay, pain, or opioid use, or improve quality of life, when compared with standard therapy and placebo in children with sickle cell disease (89399,98283,101356). Oral magnesium has not been evaluated for this purpose.
• Stillbirth. Magnesium administered during pregnancy does not reduce stillbirth risk. Details: A meta-analysis of clinical research shows that magnesium supplementation does not significantly decrease the risk of stillbirths when administered during pregnancy (60925,60978).
• Tetanus. Intravenous magnesium sulfate does not seem to improve outcomes in patients with this condition. Details: A meta-analysis of clinical research shows that intravenous magnesium sulfate does not reduce mortality when compared with placebo or diazepam in patients with tetanus (61020). While some research shows that magnesium reduces the duration of hospitalization and the need for ventilation when compared with diazepam (61170), magnesium does not seem to improve these outcomes when compared with placebo (60860).
• Traumatic brain injury (TBI). Magnesium does not improve clinical outcomes in patients with moderate to severe TBI. Its effect in patients with concussions is unclear. Details: A meta-analysis of four clinical trials shows that treatment with magnesium does not significantly improve neurological outcomes or reduce the risk of mortality when compared with placebo in patients with moderate to severe TBI (60905). A small observational cohort study in adolescents with concussions has found that adding oral magnesium 400 mg twice daily for 5 days to standard treatment with acetaminophen and ondansetron is associated with a trend toward reduced symptom severity when compared with standard treatment alone (104401). The validity of this study is limited by its observational nature and small cohort size.

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alcohol use disorder. Intravenous magnesium does not seem to help reduce symptoms of alcohol withdrawal but may reduce the duration of alcoholic delirium. Details: Preliminary clinical research shows that administration of four intramuscular injections of magnesium sulfate 2 grams at 6-hour intervals does not reduce symptoms of alcohol withdrawal when compared with saline (61063). A small observational study in patients with alcoholic delirium has found that administering magnesium sulfate IV 50 mg/kg every 8 hours, in addition to usual sedation, is associated with a reduction of delirium by approximately 2 days, or 4 days when given every 12 hours in addition to dexmedetomidine, when compared with usual sedation alone (111180). However, half of patients had hypomagnesemia at baseline; it is unclear if effects would be similar for patients with normal magnesium levels. Oral magnesium has not been evaluated for this purpose.
• Allergic rhinitis (hay fever). Although there has been interest in using oral magnesium for allergic rhinitis, there is insufficient reliable information about the clinical effects of magnesium for this purpose.
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral magnesium is beneficial in children with ADHD. Details: Children with ADHD seem to have lower magnesium levels in their blood and hair (9969,100262,100263). A small clinical study in children aged 7-12 years with ADHD and magnesium deficiency shows that taking magnesium aspartate and lactate 6 mg/kg daily for 6 months might improve hyperactivity and magnesium levels when compared with control (1189). Another small clinical study in children with ADHD but without magnesium deficiency shows that taking magnesium 6 mg/kg daily along with vitamin D 50,000 IU weekly for 8 weeks may modestly improve emotional problems, but not inattention or hyperactivity, as measured on the strength and difficulties questionnaire (SDQ), when compared with placebo (105914).
• Back pain. It is unclear if oral or intravenous magnesium is beneficial for acute or chronic back pain in adults. Details: One open-label clinical study in adults with acute low-back pain shows that taking magnesium 365 mg once daily in addition to taking etodolac 400 mg twice daily for 10 days does not further reduce pain when compared with taking etodolac alone (105913). Magnesium has also been tried for chronic back pain. A small clinical study in patients with chronic low-back pain shows that receiving magnesium sulfate 1 gram in 250 mL normal saline intravenously every 4 hours for 2 weeks, followed by magnesium gluconate 100 mg and magnesium oxide 400 mg by mouth daily for 4 weeks, reduces pain severity when compared with placebo (90035). It is unclear if oral magnesium used alone is beneficial.
• Bariatric surgery complications. It is unclear if oral magnesium supplementation improves metabolic parameters after bariatric surgery. Details: A retrospective study of over 3000 post-bariatric surgery patients suggests that those who take oral magnesium supplements providing 100-450 mg elemental magnesium daily may have improved metabolic parameters over 4 years of follow-up. When patients taking magnesium supplements were compared with those not taking supplements, 11% and 18% had type 2 diabetes, respectively, 30% and 42% had hypertension, respectively, and 16% and 23% had elevated low-density lipoprotein (LDL) cholesterol levels, respectively. For patients with hypomagnesemia at baseline, supplementation seemed to result in greater benefits (108968).
• Bipolar disorder. Taking magnesium orally might improve manic symptoms in some people with bipolar disorder; however, it is unclear how it compares to current standard of care. Details: One preliminary clinical study shows that magnesium 40 mEq daily (Magnesiocard) for 32 weeks has similar effects to lithium in up to 50% of patients treated for rapid cycling bipolar affective disorder (61022). Another preliminary clinical study shows that magnesium oxide 375 mg orally daily plus verapamil 80 mg taken four times daily reduces manic symptoms more effectively than verapamil alone in patients with mania (60742).
• Cancer-related neuropathic pain. It is unclear if intravenous magnesium is beneficial for this condition. Details: Single 500 mg to 1 gram doses of magnesium sulfate seem to relieve neuropathic pain for up to four hours when compared to baseline (6846). The validity of this finding is limited by the lack of a comparator group.
• Cardiac arrest. Intravenous magnesium does not seem to be helpful in cardiac arrest; however, the risk of sudden cardiac death seems to be inversely correlated to higher plasma magnesium levels or dietary intake. It is unclear if magnesium supplementation is associated with similar risk reduction. Details: Administering magnesium intravenously doesn't seem to improve successful resuscitation in people with cardiac arrest (1190). However, higher plasma magnesium levels and higher dietary magnesium intake might reduce the risk of sudden cardiac death, possibly by protecting against fatal ventricular arrhythmias. In the Nurses' Health Study, the risk of sudden cardiac death was 77% lower in females with the highest quartile of plasma magnesium levels when compared with the lowest quartile. Also, the risk was 37% lower in females with the highest quartile of dietary magnesium intake when compared with the lowest quartile (17132).
• Cardiovascular disease (CVD). Evidence regarding the effect of dietary magnesium on CVD risk is conflicting. Details: Epidemiological research in some populations shows that increased dietary magnesium intake is associated with decreased mortality due to strokes, coronary heart disease, ischemic heart disease, and heart failure, but other epidemiological research does not show any effect on these risks (89391,90003,90009,90030,90036,103735). Reasons for the discrepancies may be related to serum levels of magnesium at baseline, risk of cardiovascular disease at baseline, use of concomitant medications such as diuretics, or the presence of concomitant conditions such as kidney dysfunction. A population analysis conducted in Denmark has found that magnesium intake from drinking water may be associated with cardiovascular mortality. The overall risk of cardiovascular death and death due to stroke was reduced by 4% in the lowest 3 quintiles of intake when compared with the highest quintile. However, the risk of death due to acute myocardial infarction was increased by 22% in the lowest quintile when compared with the highest (108726). The relevance of these results is unclear, given that the main dietary source of magnesium is food rather than drinking water.
• Chronic fatigue syndrome (CFS). Limited evidence suggests that magnesium may help improve CFS symptoms, but this is controversial. Details: In people with low red blood cell magnesium, there is some evidence that intramuscular injections of 1 gram magnesium sulfate given once weekly for 6 weeks might improve CFS symptoms (7556). However, there is additional evidence that most patients with CFS have normal magnesium stores, and measurement of red cell magnesium is a poor indicator of total magnesium stores (7557,8084,8085,8086,8087).
• Chemotherapy-induced leukopenia. It is unclear if oral magnesium is beneficial in pediatric patients at risk for cisplatin-induced febrile neutropenia. Details: A small clinical study in children with solid tumors aged 9 years and older shows that taking magnesium 250 mg daily while receiving cisplatin-based chemotherapy reduces febrile neutropenia by 47% and septic shock by 57% when compared with not receiving magnesium. Results from this study suggest that four pediatric patients need to take oral magnesium to avoid one case of febrile neutropenia (104394).
• Chemotherapy-induced nephrotoxicity. It is unclear if intravenous magnesium is beneficial for chemotherapy-induced nephrotoxicity. Details: A meta-analysis of several lower quality clinical studies in adults in Japan with cancer receiving cisplatin shows that pretreatment with intravenous magnesium sulfate 5 to 20 mEq reduces the odds of chemotherapy-induced nephrotoxicity in a dose-dependent manner when compared to standard hydration therapy (115726). The validity of these findings is limited by heterogenous methods between clinical trials, including types of cancer, definitions of nephrotoxicity, and use of other nephroprotective therapies.
• Chronic obstructive pulmonary disease (COPD). Intravenous, but not nebulized, magnesium may be helpful in acute exacerbations of COPD. Details: Administering magnesium sulfate intravenously, 1.2-2.5 grams over 20 minutes, might be helpful for treating acute exacerbations of COPD (1208,6844,103733). Also, giving magnesium sulfate 2 grams intravenously seems to improve exercise capacity when compared with placebo (89384). A meta-analysis of studies using intravenous magnesium sulfate for COPD exacerbations shows that it reduces hospital admission and mean length of stay and improves dyspnea scores when compared with placebo. Based on the relative risk identified in the included studies, seven patients would need to receive intravenous magnesium to prevent one hospitalization. However, intravenous magnesium sulfate does not change the need for non-invasive ventilation and the available research did not evaluate intensive care unit (ICU) admission (108967). Nebulized magnesium has also been evaluated. In patients experiencing a COPD exacerbation, clinical research shows that administering nebulized magnesium sulfate with albuterol three times at 30-minute intervals does not improve pulmonary function as measured by the forced expiratory volume in 1 second (FEV1) when compared with placebo (89393). Also, a meta-analysis of a small number of low-quality studies shows that nebulized magnesium does not reduce hospital admission or the need for ventilatory support, although it might modestly improve dyspnea scores and reduce ICU admissions, when compared with placebo (108967).
• Cluster headache. It is unclear if a single intravenous dose of magnesium sulfate is beneficial for cluster headaches. Details: Administering magnesium sulfate intravenously, 1 gram over 5 minutes, seems to improve cluster headaches when compared with baseline(1184). The validity of this finding is limited by the lack of a comparator group.
• Cognitive impairment. It is unclear if oral magnesium is beneficial for cognitive impairment. Details: A large observational study in adults with end-stage renal disease on hemodialysis suggests that serum magnesium levels of 20.2-22.3 mg/dL are associated with the lowest odds of mild cognitive impairment, while serum magnesium levels below and above that range of values are associated with increased odds of mild cognitive impairment (111695).
• Coronary heart disease (CHD). It is unclear if magnesium supplementation is beneficial for CHD. Details: Clinical research shows that magnesium oxide 800-1200 mg daily for 3 months reduces platelet-dependent thrombosis by 35% when compared with placebo in patients with CHD (60759). It is unclear if this effect improves clinical outcomes. The effect of magnesium supplementation on coronary artery calcium has also been studied. A meta-analysis of 3 clinical studies in 196 patients with chronic kidney disease (CKD) shows that taking magnesium or increasing the concentration of magnesium in dialysate does not improve coronary artery calcification (CAC) scores when compared with standard therapy. However, magnesium reduced carotid intima-media thickness (111179). Similarly, a large clinical study in patients with CKD shows that taking slow-release magnesium hydroxide (Mablet, Denmark) 360 mg twice daily for 12 months does not slow the progression of CAC scores when compared with placebo (111178). This study may not have been adequately powered to detect a difference between groups.
• Coronavirus disease 2019 (COVID-19). It is unclear if oral magnesium is beneficial for COVID-19. Details: A small clinical study in patients hospitalized with moderate COVID-19 shows that taking magnesium 300 mg daily for the duration of hospitalization reduces the number of patients requiring oxygen therapy but not the duration of hospital stay when compared with placebo (114680).
• Depression. It is unclear if magnesium is beneficial for the treatment or prevention of depression in adults. Details: Some population research shows that dietary intake of elemental magnesium between 76-360 mg daily is associated with a reduced risk of depression, but there was no association with greater amounts of magnesium, and other population research shows no association at any intake level (96480,98289). For treatment of mild to moderate depression, one preliminary clinical study shows that taking magnesium chloride 2 grams orally daily for 6 weeks reduces depression scores by 56% and anxiety scores by about 52% when compared to baseline (96477). The validity of these findings is limited by the lack of a comparator group. However, a small clinical study in adults with recurrent depression shows that taking magnesium aspartate 120 mg daily for 8 weeks, along with fluoxetine, does not improve depression scores when compared with patients taking fluoxetine and placebo (111185). Similarly, a very small crossover clinical study in adults with mild or moderate treatment-resistant depression shows that administering a single dose of IV magnesium sulfate 4 grams does not improve depression scores when compared with an infusion of 5% dextrose (96481). However, scores were evaluated 24 hours post-infusion which may be too soon to detect improvement. Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that elemental magnesium in doses of 100-400 mg is not recommended for adjunctive or monotherapy use in patients with depression (110318).
• Diabetic foot ulcers. Oral magnesium has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with grade 3 diabetic foot ulcers shows that taking magnesium oxide 250 mg plus vitamin E 400 IU daily for 12 weeks modestly reduces ulcer size when compared with placebo (101436). It is unclear if this effect is due to magnesium, vitamin E, or the combination.
• Exercise-induced muscle soreness. It is unclear if oral magnesium reduces muscle soreness in adults after resistance training. Details: A very small study in healthy adults, ages 19-23, shows that taking magnesium glycinate 350 mg daily for 10 days seems to reduce muscle soreness after bench press exercise when compared with placebo (104399).
• Fetal and premature infant mortality. It is unclear if antenatal intravenous (IV) magnesium sulfate administration reduces the risk of fetal and premature infant mortality. Details: Two meta-analyses of up to 7 clinical studies in patients at risk of preterm birth shows that antenatal IV magnesium sulfate administration does not reduce the risk of fetal or neonatal death when compared with placebo (114675,114681).
• Fibromyalgia. It is unclear if oral magnesium is beneficial for this condition. Details: A small clinical study shows that taking magnesium chloride orally 100 mg once daily for one month reduces mild to moderate, but not severe, stress associated with fibromyalgia when compared with placebo. It also reduces pain levels, but not to a clinically significant extent, and it does not affect sleep, fatigue, or quality of life (108964). Another small clinical study shows that taking magnesium citrate 300 mg daily for 8 weeks improves some symptoms of fibromyalgia, such as number of tender points and depression, when compared to baseline (89385). The validity of this finding is limited by the lack of a comparator group. A small clinical study shows that taking a combination of magnesium hydroxide and malic acid (Super Malic tablets) orally decreases fibromyalgia-related pain and tenderness in some patients when compared with placebo (3262). It is unclear if this effect is due to magnesium, malic acid, or the combination.
• Fractures. Population research suggests that higher intakes of magnesium may reduce fracture risk. Details: Observational research has found that higher dietary and supplemental magnesium intake is associated with a 34% lower odds of fracture when compared with lower magnesium intake (101395).
• Gastric cancer. Population research suggests that higher intakes of magnesium may reduce gastric cancer risk. Details: Observational research has found that higher dietary and supplemental magnesium intake is not associated with a reduced risk for gastric cancer when compared with lower intake (103730).
• Hearing loss. Oral magnesium may prevent and improve hearing loss due to environmental factors or loud noises. Details: Clinical research in healthy military recruits shows that taking magnesium aspartate 167 mg daily for 2 months prevents hearing loss from exposure to loud noises during basic military training when compared with placebo (1205). Also, in patients with acute-onset hearing loss that was not caused by environmental factors, taking magnesium aspartate 167 mg daily for 8 weeks seems to improve hearing loss when compared with placebo (60813).
• Hypertension. Oral magnesium supplementation may modestly reduce blood pressure, although these changes are not likely to be considered clinically significant. Details: Most research shows that taking oral magnesium supplements in daily doses that are at least as high as the Recommended Dietary Allowance (RDA) for adults and up to 1000 mg daily can lower diastolic blood pressure by about 2 mmHg in adults with or without hypertension (1192,1199,9465,15165,18111,96482). Significantly lower doses do not seem to have this effect (1180,1195,1197,8098). The effect of magnesium on systolic blood pressure is conflicting. Two meta-analyses shows that taking magnesium 212-970 mg daily does not lower systolic blood pressure in patients with or without hypertension (15165,115728). However, additional meta-analyses show that taking magnesium 120-970 mg daily can lower systolic blood pressure in a dose-dependent manner by about 2-4 mmHg in patients with or without hypertension (18111,96482). The reasons for these discrepant findings are unclear but may be due to heterogenous methods, including dose and duration among clinical studies. In 2022, the US Food and Drug Administration (FDA) approved a qualified health claim stating that inconsistent and inconclusive evidence suggests that diets with adequate magnesium may reduce the risk of high blood pressure. Products bearing this claim must provide at least 84 mg of magnesium daily, but no more than 350 mg daily (107451).
• Hypokalemia. It is unclear if intravenous or oral magnesium is beneficial for hypokalemia in patients with normal magnesium levels. Details: A preliminary retrospective observational study in patients with hypokalemia and unknown serum magnesium levels has found that administering oral or intravenous magnesium is not associated with improved time to normalization of serum potassium levels when compared with no magnesium treatment (110049). However, hypokalemia with concurrent hypomagnesemia can impede potassium repletion and exacerbate hypokalemia-induced rhythm disturbances. Standard of care in patients with hypokalemia and known hypomagnesemia includes prompt treatment with magnesium (110063).
• Impaired glucose tolerance (prediabetes). It is unclear if oral magnesium is beneficial for prediabetes. Details: Preliminary clinical research in patients with prediabetes shows that taking magnesium oxide 250 mg orally daily for 12 weeks does not improve fasting blood glucose levels, insulin resistance, or glycated hemoglobin (HbA1C) levels when compared with placebo. Taking magnesium also did not affect blood pressure, body weight, triglyceride levels, or low-density lipoprotein cholesterol levels; however, it did modestly improve high-density lipoprotein cholesterol levels (110053).
• Insomnia. Oral magnesium may modestly improve sleep complaints in adults, but evidence is conflicting. Details: A meta-analysis of two small clinical studies in healthy older adults with or without insomnia suggests that taking magnesium reduces the time to fall asleep by an average of 17 minutes when compared with placebo (105917). However, it does not increase the time spent asleep. Also, these findings are limited by imprecision and a high risk of bias. Studies included in the analysis used elemental magnesium 500-729 mg daily (as magnesium oxide) for up to 8 weeks (102458,105917). Another small clinical study in patients with poor sleep quality and low magnesium status shows that taking elemental magnesium 320 mg (as magnesium citrate) in divided doses daily for 7 weeks does not improve sleep quality, as measured by the Pittsburgh Sleep Quality Index (PSQI), when compared with a sodium citrate placebo (102456). Magnesium has also been evaluated in combination with other ingredients. A very small crossover clinical study in patients aged 18-40 years without a sleep disorder shows that taking a combination of magnesium 300 mg, L-tryptophan 1000 mg, glycine 3000 mg, tart cherry 220 mg, and theanine 200 mg for 3 days reduces the time to fall asleep by about 24 minutes, increases total time asleep by about 22 minutes, and improves sleep efficiency, but does not improve the total time in bed or wakefulness after falling asleep when compared with cellulose placebo (111184). Another small crossover clinical study in adults with sleep disturbances shows that taking a combination of magnesium 200 mg and melatonin nightly for 4 weeks improves sleep quality, as measured by the PSQI, reduces the length of time it takes to fall asleep by about 17 minutes, and improves some other measures of sleep, such as sleep efficiency and number of awakenings, when compared with placebo. However, despite these improvements, overall sleep quality was still categorized as poor after the intervention (113670). It is unclear if these effects are due to magnesium, other ingredients, or the combination.
• Intraventricular hemorrhage. It is unclear if antenatal intravenous (IV) magnesium sulfate can reduce the risk for intraventricular hemorrhage in neonates. Details: A meta-analysis of clinical research in premature infants shows that if the mother received antenatal intravenous magnesium sulfate, the infant had a non-significant trend toward a reduced risk of intraventricular hemorrhage when compared with infants whose mothers received placebo (103727). This analysis may have been insufficiently powered to detect a difference between groups. Another meta-analysis of up to 6 clinical studies, some of which are included in the previously referenced meta-analysis, in patients at risk of preterm birth shows that maternal antenatal (IV) magnesium sulfate administration does not reduce the risk of intraventricular hemorrhage, but does reduce the risk of severe intraventricular hemorrhage by about 24% when compared with placebo (114681).
• Kidney stones (nephrolithiasis). Taking magnesium orally may prevent the recurrence of kidney stones, although evidence is conflicting. Details: Prophylactic treatment with magnesium hydroxide, 200 mg twice daily for one year, followed by 500 mg daily for another year, might decrease the recurrence rate of calcium stone formation (2007). However, magnesium oxide does not seem to benefit patients considered to be recurrent calcium stone formers when compared with placebo, no treatment, or chlorthalidone (8097,38501,61199). Magnesium oxide 300 mg in combination with vitamin B6 10 mg daily seems to decrease urinary oxalate levels in people with hyperoxaluria who have previously had kidney stones (1201), but it is unclear if this effect translates into a reduced incidence of kidney stones.
• Liver cancer. Increased dietary magnesium intake is linked with a lower risk of liver cancer. Details: Observational research in retired older Americans has found that higher dietary magnesium intake is associated with a 35% lower risk of liver cancer when compared with lower intake. This association was especially strong in persons who were moderate or heavy alcohol users (105080).
• Lung cancer. Supplemental or dietary magnesium intake does not seem to reduce the risk of lung cancer. Details: A large epidemiological cancer screening trial with a mean follow-up of over 12 years suggests there is no association between dietary or supplemental magnesium intake and the risk of lung cancer. However, dietary magnesium seems to play an important yet unclear role in lung cancer prevention when taken as part of the diet with alpha-carotene, vitamin C, vitamin E, lycopene, selenium, lutein, and zeaxanthin (112096).
• Migraine headache. Oral magnesium may help prevent migraine in some adults and children. Also, intravenous magnesium may help treat migraine in adults, but evidence is conflicting. Details: A meta-analysis of 4 low-quality clinical studies, in adults with migraine shows that magnesium 122-600 mg daily for 4-16 weeks modestly reduces migraine frequency and severity when compared with placebo(115730). However, clinical significance is unclear, and the validity of these findings is limited by heterogeneous methods between clinical trials, including type of magnesium formulation and dose, patient population, and duration. In contrast, one small clinical study shows that taking magnesium does not reduce migraine frequency and severity by at least 50% in adults when compared with placebo (10661). Limited evidence suggests that adding oral magnesium to conventional treatment may also be beneficial. A clinical study in adults with migraine living in Iran shows that taking magnesium oxide 250 mg twice daily in addition to sodium valproate 200 mg twice daily for 12 weeks modestly reduces severity and duration of migraine, but not migraine frequency, when compared with taking sodium valproate alone (105915). It is unclear if these improvements would be considered clinically significant. For treatment of migraine, some adults with normal magnesium levels respond to intravenous (IV) magnesium sulfate 1 gram over 5 minutes, but most patients who benefit have low magnesium levels at baseline (1185,6844). Effects of IV magnesium in patients with unknown magnesium levels are conflicting. Some preliminary clinical research shows that magnesium 1-2 grams IV alleviates acute migraine for up to 2 hours, but other research has found no benefit (89388,97493,98285). In children, treatment with magnesium oxide orally 15 mg/kg daily in 3 divided doses for up to 16 weeks reduces the frequency and severity of migraine headaches when compared with placebo (10663). However, adding magnesium sulfate 400 mg orally daily to ibuprofen or acetaminophen does not further reduce migraine severity in children (89396).
• Miscarriage. Oral magnesium has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in pregnant adults with threatened miscarriage between the 6th and 13th week of gestation shows that taking a specific combination product (DAV HA, Lo.Li pharma s.r.l) containing magnesium 450 mg, alpha-lipoic acid, hyaluronic acidvitamin B6, and vitamin D daily in combination with conventional treatment of vaginal progesterone over 2 weeks of observation results in a faster resorption of the subchorionic hematoma and faster decrease of patient-reported vaginal bleeding, abdominal pain, and uterine contractions when compared with vaginal progesterone alone (113893). It is unclear if these effects are due to magnesium, other ingredients, or the combination. Additionally, the validity of these findings is limited by the lack of a placebo in the control group.
• Myocardial infarction (MI). Research on the effects of intravenous or oral magnesium after myocardial infarction are conflicting. Details: Administering magnesium intravenously doesn't seem to reduce mortality after an acute MI (8999,13357,13358,13359,13360,19990,60872,61082), although there is some conflicting evidence from a meta-analysis of clinical research that shows that intravenous magnesium sulfate may reduce short-term mortality by 55% when compared with placebo (60795,60895). Clinical research with oral magnesium supplementation has found no benefit (1198,6844).
• Neonatal encephalopathy. Intravenous magnesium may improve short-term outcomes in neonates with encephalopathy. Details: A meta-analysis of clinical research shows that intravenous magnesium may improve short term outcomes of neonatal encephalopathy (hypoxic ischemic encephalopathy, HIE). However, long term outcomes are not affected (90025).
• Nocturnal leg cramps. It is unclear if oral magnesium is helpful for nocturnal leg cramps. Details: Some clinical research in adults with nocturnal leg cramps shows that taking magnesium oxide 865 mg daily at bedtime for 4 weeks does not reduce the frequency of leg cramping episodes when compared with placebo (96478). However, four weeks may be too short a time to see a benefit. In other clinical research, taking oral magnesium oxide monohydrate 226mg daily at bedtime for 60 days reduces the frequency of leg cramps when compared with placebo. This reduction was not seen after 30 days. Magnesium also reduced cramp duration and improved sleep quality, but did not affect pain scores, at 60 days when compared with placebo (106919).
• Nonalcoholic fatty liver disease (NAFLD). Oral magnesium hydroxide has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in adults with NAFLD shows that taking magnesium hydroxide 150 mg and L-carnitine 2000 mg daily for 16 weeks does not improve liver stiffness scores when compared with baseline or controls who took placebo for 8 weeks followed by this magnesium and L- carnitine combination for 8 weeks. Taking magnesium and L-carnitine also did not improve levels of aspartate aminotransferase (AST) or alanine transaminase (ALT) when compared to baseline (111177).
• Obesity. Evidence on the use of magnesium for weight loss in obese patients is conflicting; any benefit is likely small at best. Details: A meta-analysis of 7 clinical studies in obese patients shows that taking magnesium reduces body mass index (BMI) by 0.3 when compared with control (103723). Another meta-analysis of 7 studies in obese patients shows that while magnesium supplementation does not reduce weight, it reduces waist circumference by 2 cm when compared with placebo (103729). Interestingly, subgroup analyses did not find that the dose of magnesium or baseline magnesium levels impacted effectiveness. One subgroup analysis found that magnesium supplementation lasting 12 weeks or less seemed to be more beneficial for obesity than supplementation lasting longer than 12 weeks (103723).
• Overall mortality. It is unclear if oral or IV magnesium reduces the risk of overall mortality. Details: A meta-analysis of heterogeneous observational studies has found that increased dietary magnesium intake, but not supplemental magnesium intake, is associated with a modestly reduced risk of overall mortality (105073). A meta-analysis of 3 small, low-quality clinical studies in ICU patients shows that administering IV magnesium 24-30 mmol or as a target-directed dose for 3 days reduces overall mortality when compared with patients who did not receive magnesium (111290). However, some studies included patients with hypomagnesemia; it is unclear if effects would be similar for patients with normal levels of magnesium.
• Osteoarthritis. Population research has not found a link between magnesium intake and osteoarthritis risk. Details: Observational research has found that dietary and supplemental magnesium intake is not associated with the risk of developing osteoarthritis (101395).
• Pain (acute). It is unclear if locally injected or intravenous magnesium is helpful for acute pain. Details: Preliminary clinical research in patients with renal colic shows that intravenous (IV) magnesium sulfate, 50 mg/kg infused over 20 minutes, is as effective as IV morphine sulfate 0.1 mg/kg for controlling acute renal pain at 20 minutes after the dose (107367). Magnesium has also been evaluated in a dental procedure. A single-center clinical study in India in adults with irreversible pulpitis requiring a root canal shows that a local injection of 0.2 mL of 10% magnesium sulfate with lidocaine and epinephrine reduces perioperative pain when compared to lidocaine with epinephrine alone (115729).
• Pain (chronic). Population research suggests that higher intakes of magnesium may modestly reduce the risk for chronic pain. Details: A cross-sectional observational study has found that increased magnesium intake is associated with a 7% to 8% reduced risk for chronic pain. The association was found to be stronger in females than in males (103732).
• Parturition. It is unclear if topical magnesium is beneficial for labor duration. Details: A single-center clinical study in Iranian adults shows that applying 10 mL of a 50% magnesium sulfate solution directly to the cervix during the active phase of labor reduces the time to vaginal delivery by approximately 1.5 hours and improves the childbirth experience, as reported by patients, when compared with placebo. However, clinical significance is unclear (115727).
• Perioperative anxiety. It is unclear if oral magnesium is beneficial for perioperative anxiety. Details: Preliminary clinical research in adults undergoing open heart surgery shows that taking magnesium oxide 250 mg orally twice daily during hospitalization moderately improves anxiety and depression scores when compared with no magnesium therapy. Magnesium therapy was held for the 2 days immediately following surgery (110054).
• Physical performance. Oral magnesium may modestly improve physical performance in otherwise healthy, elderly females. Details: Clinical research in otherwise healthy elderly females shows that taking a magnesium oxide supplement (Easymag, Sanofi-Aventis) 900 mg daily for 12 weeks modestly improves walking speed and chair stand speed in elderly females when compared with no treatment (90026).
• Polycystic ovary syndrome (PCOS). It is unclear if oral magnesium is beneficial for improving metabolic indices in patients with PCOS. Details: Two small clinical studies in patients with PCOS show that taking magnesium oxide orally, 250 mg daily for 8 weeks, does not affect insulin resistance, beta-cell function, lipid levels, or insulin sensitivity when compared with placebo (103725,105887). Other clinical research in patients with PCOS shows that taking magnesium oxide orally, 250 mg daily for 10 weeks, improves subjective measures of quality of life, fatigue, and emotional functioning, but not objective measures such as alopecia, abnormal uterine bleeding, or acne, when compared with placebo (108965). A clinical study using a combination of magnesium 250 mg with vitamin E 400 mg daily for 12 weeks shows a modest reduction in insulin resistance, insulin levels, and triglyceride levels, but not other lipid levels, when compared with placebo (100264). It is unclear if these beneficial effects are due to magnesium, vitamin E, or the combination.
• Postoperative nausea and vomiting (PONV). It is unclear if intravenous (IV) magnesium is beneficial for PONV due to mixed results from clinical research. Details: A meta-analysis of 5 clinical studies in adults undergoing surgery with general anesthesia shows that administering IV magnesium sulfate intraoperatively reduces PONV (114676). However, a meta-analysis of 20 clinical studies in adults undergoing surgery with general anesthesia shows that administering IV magnesium perioperatively does not reduce the incidence of PONV (114678). A moderate-sized clinical study conducted in China in older adults undergoing total knee arthroplasty shows that administering intravenous magnesium sulfate 40 mg/kg prior to anesthesia induction then 15 mg/kg during surgery reduces the incidence of postoperative vomiting but not postoperative nausea when compared with control (113677). The reasons for these discrepant findings are unclear but may be explained by differences in magnesium regimens, anesthesia protocols, and surgical populations studied.
• Postoperative recovery. It is unclear if intravenous (IV) magnesium is beneficial for postoperative recovery. Details: A moderate-sized clinical study conducted in China in older adults undergoing total knee arthroplasty shows that administering IV magnesium sulfate 40 mg/kg prior to anesthesia induction then 15 mg/kg during surgery does not reduce extubation time, time spent in the post-anesthesia care unit (PACU), or duration of hospital stay when compared with control (113677). Additionally, a meta-analysis of 3 different clinical studies in adults undergoing surgery with general anesthesia shows that administering IV magnesium intraoperatively does not reduce extubation time (114676).
• Postoperative sleep disturbance. It is unclear if oral magnesium is beneficial for postoperative sleep disturbances. Details: Preliminary clinical research in adults undergoing open heart surgery shows that taking magnesium oxide 250 mg orally twice daily during hospitalization moderately improves sleep scores when compared with no magnesium therapy. Magnesium therapy was held for the 2 days immediately following surgery (110054).
• Postoperative sore throat. It is unclear if topical magnesium sulfate is beneficial for reducing sore throat pain after endotracheal intubation. Details: Preliminary clinical research in patients undergoing endotracheal intubation for surgery shows that using a gargle containing magnesium sulfate 20% with lidocaine, 20 minutes before anesthesia induction, is less effective for reducing sore throat pain than a gargle containing dexmedetomidine and lidocaine (112779). The study did not include a comparison to lidocaine alone.
• Pregnancy-related leg cramps. It is unclear if oral magnesium reduces leg cramps during pregnancy; evidence is conflicting. Details: One small clinical study in patients with pregnancy-related leg cramps shows that taking magnesium bisglycinate chelate 300 mg daily for 4 weeks reduces the frequency and intensity of leg cramps when compared with placebo (99318). A smaller clinical study in this population shows that taking a specific mixture of magnesium lactate and citrate (Nycoplus Magnesium) providing elemental magnesium 120 mg in the morning and 240 mg in the evening for 3 weeks reduces the frequency of cramps when compared with placebo (1194). However, not all research agrees. One small clinical study using this same supplement and dose for 2 weeks found no benefit when compared with placebo (17463). It is possible that a 2-week duration of treatment is too short to be beneficial. Finally, a meta-analysis of these studies and one other more recent clinical study shows that taking magnesium does not reduce the frequency or improve the resolution of pregnancy-related leg cramps when compared with placebo (105916). This analysis may not have been adequately powered to detect a difference between treatment groups.
• Pre-procedural sedation. It is unclear if intravenous magnesium is beneficial when administered in addition to other medications used for sedation during surgery. Details: A moderate-sized study of adults aged 65-79 years old undergoing endoscopic retrograde cholangiopancreatography (ERCP) shows that administering a single intravenous bolus of magnesium sulfate 40 mg/kg prior to the procedure reduces intraoperative propofol requirements by about 21% and reduces some peri-procedural adverse events including the incidence of respiratory depression and involuntary movement when compared with control. However, there were no differences in recovery time, hemodynamic parameters, or the incidence of hypotension, bradycardia, perioperative nausea or vomiting, lethargy, or arrythmias (111694). Another moderate-sized study in older adults undergoing total knee arthroplasty shows that administering intravenous magnesium sulfate 40 mg/kg prior to anesthesia induction then 15 mg/kg during surgery does not reduce the need for medications used for anesthesia induction, intraoperative maintenance propofol requirements, or recovery time when compared with control. However, magnesium sulfate does seem to reduce the amount of remifentanil required for intraoperative anesthesia maintenance and increase norepinephrine requirements when compared with control (113677).
• Preterm labor. The use of magnesium sulfate to inhibit uterine contractions in preterm labor (tocolysis) is controversial. However, its use for the purpose of fetal neuroprotection for up to 48 hours is supported by the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine. Details: Magnesium is given intravenously (IV) during preterm labor in an effort to improve fetal neurological outcomes, such as to reduce the risk of cerebral palsy and motor dysfunction in the infant (60915,60927,60931,61001,97485,103734,103754,114681). The typical dosage of magnesium sulfate is 4 grams infused IV over 10-30 minutes, followed by a maintenance infusion of 1-4 grams/hour for 48 hours or until birth. Use beyond 5-7 days has been associated with hypocalcemia and bone abnormalities in the fetus (15,12590,12594). Some meta-analyses of clinical research suggest that magnesium sulfate is more effective at delaying delivery by 48 hours when compared with oxytocin receptor blockers, nitrates, beta-mimetics, and/or placebo (20263,61021). However, an additional meta-analysis of several clinical studies shows that magnesium sulfate 4 or 6 grams IV is not more effective at delaying preterm labor by 48 hours when compared with nifedipine (115639). The reason for these discrepant findings are unclear, but may be related to the heterogenous methods between clinical trials, including dose and duration.
• Pseudoxanthoma elasticum (PXE). It is unclear if oral magnesium is beneficial for PXE. Details: Preliminary clinical research in patients with PXE shows that taking magnesium oxide 800 mg (500 mg of elemental magnesium) twice daily for one year tends to reduce calcification of elastic skin fibers when compared with placebo, but the effect is not statistically significant (101393). This study was limited by small size and insufficient power to detect smaller effects.
• Restless legs syndrome (RLS). It is unclear if oral magnesium is beneficial for RLS. Details: Some observational research has found that hypomagnesemia is associated with RLS; however, not all research agrees (8096,9472). Preliminary clinical research in adults with RLS who are beginning treatment with pramipexole shows that also taking magnesium oxide 250 mg orally daily for 2 months moderately improves RLS scores and sleep quality scores when compared with pramipexole and placebo (110052). Other low-quality clinical research in adults with RLS or periodic limb movement during sleep shows that taking magnesium 12.4 mmol orally in the evening for 4-6 weeks decreases movement and increases sleep when compared with baseline (9466). The validity of this finding is limited by the lack of a comparator group.
• Sarcopenia. It is unclear if oral magnesium is beneficial for the prevention or treatment of sarcopenia. Details: Population research in older adults has found that lower dietary intake of magnesium is associated with sarcopenia. However, the effect of magnesium supplementation on sarcopenia prevention or treatment has not been evaluated (110055). Magnesium has been evaluated in combination with other ingredients for treatment of sarcopenia. A small clinical study in elderly individuals with sarcopenia undergoing a diet and exercise program shows that taking a combination supplement containing magnesium 300 mg, carnosine, hydroxymethylbutyrate, lactoferrin, and sodium butyrate daily for 4 months increases muscle mass, as measured by the skeletal muscle index, and improves measures of muscle function, including handgrip muscle strength, chair test, and walking speed, when compared with placebo (114682). It is unclear if these effects are due to magnesium, other ingredients, or the combination.
• Sepsis. It is unclear if intravenous magnesium is beneficial for sepsis. Details: A very large observational study in patients with sepsis and hypomagnesaemia or normomagnesemia in the intensive care unit (ICU) suggests that administering intravenous magnesium sulfate 2 or 4 grams within 24 hours of admission reduces 28-day all-cause mortality from 25% in patients who did not use magnesium sulfate to 20% in those who were administered magnesium sulfate, regardless of baseline serum magnesium level and other baseline characteristics. Administration of intravenous magnesium sulfate in this population may also reduce ICU mortality by 4%, in-hospital mortality by 3%, and the use of renal replacement therapy by 3% but also seems to increase the length of ICU and hospital stay when compared with patients who did not use magnesium sulfate (113676). The validity of these results is limited by the observational nature of the study.
• Sleep deprivation. Oral magnesium has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A very small clinical study in sleep-deprived recreational athletes shows that taking a combination of magnesium 1350 mg, zinc 90 mg, and vitamin B6 31.5 mg for 3 nights at bedtime does not change sleep quality, subjective sleepiness, mood, or fatigue the next day when compared with placebo (113655).
• Stroke. Increased dietary magnesium may decrease stroke risk, and using a magnesium-containing salt substitute may improve neurological performance post-stroke. However, intravenous magnesium has not demonstrated benefit. Details: Most population research has found that increased dietary intake of magnesium is associated with decreased stroke risk and decreased mortality from stroke (9001,9002,90013,90030,90036,92107,103736). In patients who have had a stroke, a preliminary clinical study shows that using a salt substitute providing the Dietary Reference Intake (DRI) of magnesium and potassium for 6 months improves neurological performance when compared with using regular salt (97491). However, intravenous (IV) magnesium does not seem to be beneficial in patients who have had a stroke. Large prospective clinical trials show that IV magnesium given within 12 hours of acute stroke does not reduce mortality or disability in most patients when compared with placebo. However, one subgroup analysis suggested that IV magnesium might benefit patients with lacunar (non-cortical) stroke (13361,90021). IV magnesium also doesn't seem to reduce cardiovascular complications after acute stroke. A secondary analysis of a clinical trial in patients after ischemic and hemorrhagic stroke shows that giving IV magnesium does not reduce serious cardiac adverse events when compared with placebo (104393). Another secondary analysis of this trial shows that giving IV magnesium prior to arrival at the hospital and within 2 hours of a hemorrhagic stroke does not reduce hematoma volume on hospital arrival, hematoma expansion during hospital admission, or functional outcomes at 3 months (108733).
• Subarachnoid hemorrhage. Intravenous magnesium sulfate may reduce the risk of adverse outcomes in people with subarachnoid hemorrhage, but evidence is conflicting. Details: There is mixed evidence regarding the effect of magnesium sulfate in managing aneurysmal subarachnoid hemorrhage. One meta-analysis of clinical research shows that intravenous magnesium sulfate 64-144 mmol/day for 10-18 days reduces the risk of poor outcomes following aneurysmal subarachnoid hemorrhage, including death, vegetative state, or dependency, by 46% when compared with control (60932). Also, meta-analyses of clinical research show that intravenous magnesium reduces the risk of delayed cerebral ischemia by 27% when compared with placebo (60944,89398). However, these results were not confirmed in other meta-analyses (60973,90034).
• Thrombocytopenia. It is unclear if intravenous magnesium sulfate is beneficial in patients with thrombotic thrombocytopenic purpura (TTP). Details: Addition of intravenous magnesium sulfate as a 6-gram loading dose followed by 6 grams infused over 24 hours for 3 days, to standard treatment for TTP does not reduce the time to normalization of the platelet count, the incidence of TTP-related organ dysfunction, or the recurrence rate, when compared with standard treatment alone (112777). This study may have been underpowered to detect a difference.
• Urinary incontinence. Although there has been interest in using oral magnesium for urinary incontinence, there is insufficient reliable information about the clinical effects of magnesium for this purpose. More evidence is needed to rate magnesium for these uses.

(Read more about MAGNESIUM)

POSSIBLY EFFECTIVE

• Cognitive function. Oral L-theanine may improve some aspects of cognitive function. It is unclear if using L-theanine in conjunction with caffeine can enhance the effects of either ingredient. Details: A single dose of L-theanine 100 mg seems to improve vigilant attention, reducing error rates in cognitive tests when compared with placebo (91747). However, taking L-theanine (Suntheanine, Taiyo Kagaku) 200 mg daily for 4 weeks does not improve verbal fluency, memory, motor speed, or executive function in an adult population, although it may moderately improve verbal fluency in a subgroup of people with lower cognitive function at baseline (101986). When L-theanine is combined with caffeine, a meta-analysis and multiple individual clinical studies show that the combination improves alertness, as well as accuracy during a test that requires switching attention between different tasks, but does not improve reaction time (38116,91750,96335,96336). Some research also shows that L-theanine plus caffeine improves cognitive performance and reduces task-induced fatigue when compared with baseline and placebo. However, it is unclear if this is due to the individual ingredients or the combination (38116,96335,96336). Some research suggests that the combination is no better than either individual ingredient alone (91747,96335,96336).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral L-theanine, taken continuously or as a single dose, improves cognition in older adults. Details: A small clinical study in healthy, Japanese adults aged 50-69 years shows that taking a specific product (Suntheanine; Taiyo International.) containing L-theanine 101 mg daily after breakfast for 12 weeks does not improve mini-mental state exam (MMSE) scores when compared with placebo. However, a single-dose analysis from this study shows that administration of L-theanine 101 mg may improve the quality of working memory and reaction times during a cognitive function test when compared with placebo (108553). Patients were permitted to consume polyphenol-rich beverages during the study period; however, consumption was not documented, limiting the validity of this finding.
• Alzheimer disease. Although there is interest in using oral theanine for Alzheimer disease, there is insufficient reliable information about the clinical effects of theanine for this condition.
• Anxiety. It is unclear if oral L-theanine is beneficial in patients with anxiety. Results of clinical research are conflicting. Details: A preliminary clinical study shows that taking a single dose of a specific L-theanine product (Suntheanine, Taiyo Kagaku) 200 mg does not reduce experimentally-induced anticipatory anxiety when compared with placebo (12188). However, another preliminary clinical study in healthy adults with stress-related anxiety shows that taking L-theanine 200 mg daily for 4 weeks reduces anxiety scale scores and sleep disturbance when compared with placebo (101986).
• Attention. It is unclear if oral theanine improves attention. Details: A small clinical study in healthy males shows that taking a single dose of L-theanine 200 mg improves selective attention similar to a single dose of caffeine 160 mg (96337). However, other small clinical studies in adults show that taking L-theanine 100-400 mg does not improve most measures of attention, especially sustained attention or attention in executive control tasks, but doses of 100-200 mg may improve performance in simple attentional tasks when compared with placebo (96338,111396). Some of these studies suggest that taking L-theanine with caffeine appears to provide more benefit than either individual ingredient alone (96337,96338).
• Attention deficit-hyperactivity disorder (ADHD). Oral L-theanine seems to improve some aspects of ADHD, including cognition and sleep. Details: Some preliminary clinical research in children with ADHD shows that taking a one-time dose of L-theanine 2.5 mg/kg increases cognition scores, but does not improve results on sustained attention or inhibitory control tests, when compared with placebo. Taking L-theanine with caffeine 2 mg/kg also increases cognition scores and improves performance on a sustained attention test, but does not improve inhibitory control, when compared with placebo (104141). Other preliminary clinical research in males aged 8-12 years with ADHD shows that taking a specific L-theanine product (Suntheanine, Taiyo Kagaku) 200 mg orally twice daily for 6 weeks increases the percent of time spent in restful sleep by about 5% and decreases the number of bouts of nocturnal activity by about 6 when compared with placebo (91744).
• Cancer. Although there is interest in using oral theanine for cancer, there is insufficient reliable information about the clinical effects of theanine for this condition.
• Chemotherapy-induced diarrhea. Oral L-theanine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with colon cancer shows that taking L-cystine 700 mg and L-theanine 280 mg (Ajinomoto Co. Inc.) orally once daily, starting one week before chemotherapy with TS-1 (Taiho Pharmaceutical) and continuing for 28 days, increases the rate of therapy completion by 49%, reduces the incidence of diarrhea by 37%, reduces appetite loss by 33%, and improves the reported tolerability of chemotherapy when compared with chemotherapy alone (96334). However, this combination does not appear to be beneficial in patients with gastric cancer, or in those with colorectal cancer receiving 4 courses of capecitabine-based adjuvant chemotherapy. (96334,101985).
• Cognitive impairment. Oral L-theanine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One very small clinical study in adults with mild cognitive impairment shows that taking a product containing L-theanine 120 mg and green tea extract 720 mg (LGNC-07, LG Household & Health Care, Ltd) orally twice daily after meals for 16 weeks modestly improves memory and attention when compared with baseline. However, taking this product does not appear to improve memory and attention when patients with self-reported memory problems, but without mild cognitive impairment, are also considered (96339).
• Depression. It is unclear if oral L-theanine is beneficial in patients with depression. Details: A small clinical study shows that taking a specific L-theanine product (Suntheanine, Taiyo Kagaku Co. Ltd.) 250 mg at bedtime for 8 weeks reduces symptoms and improves sleep quality when compared to baseline in individuals with mild major depressive disorder (MDD) (96331). The validity of these findings is limited by the lack of a comparator group. Another small clinical study in adults with MDD shows that taking L-theanine 200 mg daily with sertraline for 6 weeks reduces depression symptoms and increases remission rates but does not improve treatment response rates when compared with sertraline and placebo (112278). The validity of these effects is limited by the small sample size and short study duration. Additionally, it is unclear if the reduction in depressive symptoms is clinically significant.
• Erythema. Oral L-theanine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in healthy females with self-perceived skin sensitivity shows that taking a specific supplement containing L-theanine, ashwagandha, and saffron (InnerCalm, Arbonne) daily for 8 weeks reduces facial pigmentation when compared to baseline (111399). The validity of this finding is limited by a lack of a placebo group. It is unclear if these effects are due to L-theanine, other ingredients, or the combination.
• Generalized anxiety disorder (GAD). It is unclear if oral L-theanine is beneficial for reducing anxiety in people with GAD. Details: One small clinical study in adults with GAD shows that taking L-theanine 225 mg twice daily for 4 weeks, then 450 mg twice daily for 4 weeks, in conjunction with prescribed antidepressants, does not reduce anxiety scores when compared with antidepressants and placebo (104976).
• Hypertension. Although there is interest in using oral theanine for hypertension, there is insufficient reliable information about the clinical effects of theanine for this condition.
• Influenza. Oral L-theanine 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 green tea catechins (THEA-FLAN 90S, Ito-en Co.) 378 mg, standardized to contain epigallocatechin gallate 270 mg and L-theanine (Suntheanine, Taiyo Kagaku) 210 mg daily for 5 months reduces the risk of developing clinically diagnosed influenza when compared with placebo. However, the combination does not seem to prevent laboratory-confirmed influenza infection (54021).
• Insomnia. It is unclear if oral L-theanine is beneficial for insomnia. Details: A very small clinical study in young healthy adults with sleep quality worsened by caffeine intake shows that taking L-theanine 50 mg (Suntheanine, Taiyo Kagaku Co. Ltd) once 10 minutes before bedtime suppresses caffeine-induced elevations in wake after sleep onset time but does not improve parameters of sleep quality including sleep onset latency, sleep time, or number of times waking after sleep onset when compared with placebo (112275). L-theanine has also been studied in combination with other ingredients. A small clinical study in adults with insomnia or disturbed sleep patterns shows that a specific product (RLX2; LiveLife Biosciences AG) containing L-theanine 50 mg and a specific casein peptide, alpha-s1-casein tryptic hydrolysate, 150 mg, taken one hour before bedtime for 4 weeks, increases sleep duration by 45 minutes and improves habitual sleep efficiency and daytime dysfunction when compared with baseline (108556). Another very small clinical study in healthy adults shows that taking a combination product containing tryptophan, glycine, magnesium, tart cherry powder, and L-theanine 2 hours before bedtime decreases sleep onset latency and increases total sleep duration, leading to better sleep efficiency and reduced morning sleepiness, when compared with placebo (111184). Another combination product containing L-theanine, ashwagandha, and saffron (InnerCalm, Arbonne), taken daily for 8 weeks, seems to improve sleep quality when compared to baseline (111399). However, the validity of this finding is limited by a lack of a control group. It is unclear if the effects described above are due to L-theanine, other ingredients, or the combination.
• Obsessive-compulsive disorder (OCD). It is unclear if oral L-theanine is beneficial for OCD. Details: A small clinical study in adults with OCD shows that taking L-theanine 100 mg twice daily for 10 weeks with fluvoxamine reduces OCD symptoms, particularly obsessive symptoms, and increases the proportion of patients with a complete response to treatment but does not improve compulsive symptoms, partial response rates, or remission rates when compared with placebo and fluvoxamine (112276).
• Postoperative recovery. Oral theanine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study of adults with esophageal cancer undergoing esophagectomy shows that taking theanine 280 mg and cystine 700 mg daily, staring 4 days before surgery and continued for 13 days after surgery, does not improve measures of physical activity but does improve exercise tolerance and some measures of quality of life when compared with placebo (111400). It is unclear if these findings are due to theanine, cystine, or the combination.
• Schizophrenia. It is unclear if oral L-theanine is beneficial in patients with schizophrenia; the available evidence is limited and conflicting. Details: One small preliminary clinical study in adults with schizophrenia or schizoaffective disorder shows that taking L-theanine (Biosynergy) 200 mg orally twice daily for 8 weeks along with antipsychotic medications improves positive symptoms, anxiety, and general psychopathology symptoms, such as poor impulse control and disorientation, when compared with placebo. However, theanine does not improve general disease severity, negative symptoms, depression, cognitive function, extrapyramidal side effects, or quality of life (96341). In contrast, two small clinical studies show that taking L-theanine 400 mg (Suntheanine, BioSynergy Health Alternatives) with antipsychotics and with or without pregnenolone 50 mg daily for 8 weeks reduces negative symptoms, general psychopathology symptoms, and anxiety when compared with placebo in patients with schizophrenia or schizoaffective disorder. However, there were no improvements in positive schizophrenia symptoms, extrapyramidal side effects, or symptoms of depression (97923,112277). The inconsistency of results might be due to the small study sizes and the subjectivity of the outcomes measured.
• Stress. It is unclear if oral L-theanine is beneficial in patients with stress. Details: One very small clinical study shows that taking L-theanine 200 mg prior to a stress-inducing exam reduces tension-anxiety and may prevent blood pressure increases caused by psychological stress when compared with placebo (91746). Other preliminary clinical research in pharmacy students shows that taking theanine 200 mg twice daily for one week prior, and then for the first 10 days of a pharmacy practice period, decreases subjective stress scores when compared with placebo (91745). Another small clinical study in healthy young adults shows that drinking a beverage containing L-theanine 200 mg alone or combined with L-arginine 50 mg after a psychological stressor reduces stress, as measured by salivary alpha-amylase activity, when compared with placebo. The combination of L-arginine and L-theanine did not differ from L-theanine alone, suggesting that the combination does not act synergistically to reduce markers of stress (110393). However, not all research has been positive. A small clinical study shows that taking a specific L-theanine product (Suntheanine, Taiyo Kagaku) 200 mg induces subjective feelings of tranquility in relaxed people, but not those with experimentally-induced anticipatory anxiety, when compared with placebo (12188). Also, a small, clinical crossover study in healthy, moderately stressed adults shows that taking a single dose of a specific product (Alphawave; Ethical Naturals) containing L-theanine 200 mg prior to a stress-inducing exam does not improve anxiety at any time point when compared with placebo (108554). Due to the single-dose nature of this study, the effects of continued administration of this product are unclear. L-theanine has also been evaluated in combination with other ingredients. A small clinical study in adults with stress shows that taking a specific combination product (Mg-Teadiola, Sanofi-Aventis Group), containing green tea extract 125 mg (providing 50 mg L-theanine), magnesium 150 mg, vitamin B6 0.2 mg, vitamin B9 0.1 mg, vitamin B12 1.25 mcg, and rhodiola 222 mg, orally once daily for 28 days modestly improves stress and anxiety scores when compared with placebo. Improvements in stress scores, but not anxiety scores, appear to persist at 28 days after treatment completion (108672). It is unclear if any effects are due to L-theanine, other ingredients, or the combination.
• Tourette syndrome. It is unclear if oral L-theanine is beneficial in children with Tourette syndrome. Details: A small, nonblinded clinical study in children aged 4-17 years with untreated Tourette syndrome or with chronic tic disorder and associated symptoms of anxiety shows that taking a liquid nutritional supplement providing L-theanine 200 mg and vitamin B6 2.8 mg daily for 2 months improves scores on the Yale Global Tic Severity Scale, but does not reduce anxiety, when compared with patients receiving psychoeducation (108555). This study may have been inadequately powered to detect a difference between groups. More evidence is needed to rate theanine for these uses.

(Read more about THEANINE)

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 orally and appropriately. Oral magnesium is safe when used in doses below the tolerable upper intake level (UL) of 350 mg daily (7555). ...when used parenterally and appropriately. Parenteral magnesium sulfate is an FDA-approved prescription product (96484).

POSSIBLY UNSAFE ...when used orally in excessive doses. Doses greater than the tolerable upper intake level (UL) of 350 mg daily frequently cause loose stools and diarrhea (7555).

CHILDREN: LIKELY SAFE
when used orally and appropriately. Magnesium is safe when used in doses below the tolerable upper intake level (UL) of 65 mg daily for children 1 to 3 years, 110 mg daily for children 4 to 8 years, and 350 mg daily for children older than 8 years (7555,89396). ...when used parenterally and appropriately (96483).

CHILDREN: LIKELY UNSAFE
when used orally in excessive doses. Tell patients not to use doses above the tolerable upper intake level (UL). Higher doses can cause diarrhea and symptomatic hypermagnesemia including hypotension, nausea, vomiting, and bradycardia (7555,8095).

PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately. Magnesium is safe for those pregnant and breast-feeding when used in doses below the tolerable upper intake level (UL) of 350 mg daily (7555).

PREGNANCY AND LACTATION: POSSIBLY SAFE
when prescription magnesium sulfate is given intramuscularly and intravenously prior to delivery for up to 5 days (12592,89397,99354,99355). However, due to potential adverse effects associated with intravenous and intramuscular magnesium, use during pregnancy is limited to patients with specific conditions such as severe pre-eclampsia or eclampsia. There is some evidence that intravenous magnesium can increase fetal mortality and adversely affect neurological and skeletal development (12590,12593,60818,99354,99355). However, a more recent analysis of clinical research shows that increased risk of fetal mortality seems to occur only in the studies where antenatal magnesium is used for tocolysis and not for fetal neuroprotection or pre-eclampsia/eclampsia (102457). Furthermore, antenatal magnesium does not seem to be associated with increased risk of necrotizing enterocolitis in preterm infants (104396). There is also concern that magnesium increases the risk of maternal adverse events. A meta-analysis of clinical research shows that magnesium sulfate might increase the risk of maternal adverse events, especially in Hispanic mothers compared to other racial and ethnic groups (60971,99319).

PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in excessive doses. Tell patients to avoid exceeding the tolerable upper intake level (UL) of 350 mg daily. Taking magnesium orally in higher doses can cause diarrhea (7555). ...when prescription magnesium sulfate is given intramuscularly and intravenously prior to delivery for longer than 5 days (12592,89397,99354,99355). Maternal exposure to magnesium for longer than 5-7 days is associated with an increase in neonatal bone abnormalities such as osteopenia and fractures. The U.S. Food and Drug Administration (FDA) recommends that magnesium injection not be given for longer than 5-7 days (12590,12593,60818,99354,99355).

(Read more about MAGNESIUM)

POSSIBLY SAFE ...when used orally and appropriately, short-term. L-theanine has been used safely in clinical research in doses of up to 900 mg daily for 8 weeks (12188,36439,96331,96332,96334,96341,97923,101986,104976). There is insufficient reliable information available about the safety of L-theanine when used long-term.

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term. A specific L-theanine product (Suntheanine, Taiyo Kagaku) 200 mg twice daily has been used safely in males aged 8-12 years for up to 6 weeks (91744).

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

(Read more about THEANINE)

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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AMINOGLYCOSIDE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Concomitant use of aminoglycoside antibiotics and magnesium can increase the risk for neuromuscular weakness.  Details Both aminoglycosides and magnesium reduce presynaptic acetylcholine release, which can lead to neuromuscular blockade and possible paralysis. This is most likely to occur with high doses of magnesium given intravenously (13362).

ANTACIDS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Use of acid reducers may reduce the laxative effect of magnesium oxide.  Details A retrospective analysis shows that, in the presence of H2 receptor antagonists (H2RAs) or proton pump inhibitors (PPIs), a higher dose of magnesium oxide is needed for a laxative effect (90033). This may also occur with antacids. Under acidic conditions, magnesium oxide is converted to magnesium chloride and then to magnesium bicarbonate, which has an osmotic laxative effect. By reducing acidity, antacids may reduce the conversion of magnesium oxide to the active bicarbonate salt.

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, magnesium may have antiplatelet effects, but the evidence is conflicting.  Details In vitro evidence shows that magnesium sulfate inhibits platelet aggregation, even at low concentrations (20304,20305). Some preliminary clinical evidence shows that infusion of magnesium sulfate increases bleeding time by 48% and reduces platelet activity (20306). However, other clinical research shows that magnesium does not affect platelet aggregation, although inhibition of platelet-dependent thrombosis can occur (60759).

BISPHOSPHONATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Magnesium can decrease absorption of bisphosphonates.  Details Cations, including magnesium, can decrease bisphosphonate absorption. Advise patients to separate doses of magnesium and these drugs by at least 2 hours (13363).

CALCIUM CHANNEL BLOCKERS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Magnesium can have additive effects with calcium channel blockers, although evidence is conflicting.  Details Magnesium inhibits calcium entry into smooth muscle cells and may therefore have additive effects with calcium channel blockers. Severe hypotension and neuromuscular blockades may occur when nifedipine is used with intravenous magnesium (3046,20264,20265,20266), although some contradictory evidence suggests that concurrent use of magnesium with nifedipine does not increase the risk of neuromuscular weakness (60831). High doses of magnesium could theoretically have additive effects with other calcium channel blockers.

DIGOXIN Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Magnesium salts may reduce absorption of digoxin.  Details Clinical evidence suggests that treatment with oral magnesium hydroxide or magnesium trisilicate reduces absorption of digoxin from the intestines (198,20268,20270). This may reduce the blood levels of digoxin and decrease its therapeutic effects.

GABAPENTIN (Neurontin) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Unlikely •  Level of Evidence = B Gabapentin absorption can be decreased by magnesium.  Details Clinical research shows that giving magnesium oxide orally along with gabapentin decreases the maximum plasma concentration of gabapentin by 33%, time to maximum concentration by 36%, and area under the curve by 43% (90032). Advise patients to take gabapentin at least 2 hours before, or 4 to 6 hours after, magnesium supplements.

KETAMINE (Ketalar) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Magnesium might precipitate ketamine toxicity.  Details In one case report, a 62-year-old hospice patient with terminal cancer who had been stabilized on sublingual ketamine 150 mg four times daily experienced severe ketamine toxicity lasting for 2 hours after taking a maintenance dose of ketamine following an infusion of magnesium sulfate 2 grams (105078). Since both magnesium and ketamine block the NMDA receptor, magnesium is thought to have potentiated the effects of ketamine.

LEVODOPA/CARBIDOPA (Sinemet) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Magnesium can reduce the bioavailability of levodopa/carbidopa.  Details Clinical research in healthy volunteers shows that taking magnesium oxide 1000 mg with levodopa 100 mg/carbidopa 10 mg reduces the area under the curve (AUC) of levodopa by 35% and of carbidopa by 81%. In vitro and animal research shows that magnesium produces an alkaline environment in the digestive tract, which might lead to degradation and reduced bioavailability of levodopa/carbidopa (100265).

POTASSIUM-SPARING DIURETICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Potassium-sparing diuretics decrease excretion of magnesium, possibly increasing magnesium levels.  Details Potassium-sparing diuretics also have magnesium-sparing properties, which can counteract the magnesium losses associated with loop and thiazide diuretics (9613,9614,9622). Theoretically, increased magnesium levels could result from concomitant use of potassium-sparing diuretics and magnesium supplements.

QUINOLONE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Magnesium decreases absorption of quinolones.  Details Magnesium can form insoluble complexes with quinolones and decrease their absorption (3046). Advise patients to take these drugs at least 2 hours before, or 4 to 6 hours after, magnesium supplements.

SEVELAMER (Renagel, Renvela) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Sevelamer may increase serum magnesium levels.  Details In patients on hemodialysis, sevelamer use was associated with a 0.28 mg/dL increase in serum magnesium. The mechanism of this interaction remains unclear (96486).

SKELETAL MUSCLE RELAXANTS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = A Parenteral magnesium alters the pharmacokinetics of skeletal muscle relaxants, increasing their effects and accelerating the onset of effect.  Details Parenteral magnesium shortens the time to onset of skeletal muscle relaxants by about 1 minute and prolongs the duration of action by about 2 minutes. Magnesium potentiates the effects of skeletal muscle relaxants by decreasing calcium-mediated release of acetylcholine from presynaptic nerve terminals, reducing postsynaptic sensitivity to acetylcholine, and having a direct effect on the membrane potential of myocytes (3046,97492,107364). Magnesium also has vasodilatory actions and increases cardiac output, allowing a greater amount of muscle relaxant to reach the motor end plate (107364). A clinical study found that low-dose rocuronium (0.45 mg/kg), when given after administration of magnesium 30 mg/kg over 10 minutes, has an accelerated onset of effect, which matches the onset of effect seen with a full-dose rocuronium regimen (0.6 mg/kg) (96485). In another clinical study, onset times for rocuronium doses of 0.3, 0.6, and 1.2 mg/kg were 86, 76, and 50 seconds, respectively, when given alone, but were reduced to 66, 44, and 38 seconds, respectively, when the doses were given after a 15-minute infusion of magnesium sulfate 60 mg/kg (107364). Giving intraoperative intravenous magnesium sulfate, 50 mg/kg loading dose followed by 15 mg/kg/hour, reduces the onset time of rocuronium, enhances its clinical effects, reduces the dose of intraoperative opiates, and prolongs the spontaneous recovery time (112781,112782). It does not affect the activity of subsequently administered neostigmine (112782).

SULFONYLUREAS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Magnesium increases the systemic absorption of sulfonylureas, increasing their effects and side effects.  Details Clinical research shows that administration of magnesium hydroxide with glyburide increases glyburide absorption, increases maximal insulin response by 35-fold, and increases the risk of hypoglycemia, when compared with glyburide alone (20307). A similar interaction occurs between magnesium hydroxide and glipizide (20308). The mechanism of this effect appears to be related to the elevation of gastrointestinal pH by magnesium-based antacids, increasing solubility and enhancing absorption of sulfonylureas (22364).

TETRACYCLINE ANTIBIOTICS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Magnesium decreases absorption of tetracyclines.  Details Magnesium can form insoluble complexes with tetracyclines in the gut and decrease their absorption and antibacterial activity (12586). Advise patients to take these drugs 1 hour before or 2 hours after magnesium supplements.

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ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.  Details Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals (7687,77354). Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

CNS DEPRESSANTS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = D Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.  Details Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression (96334). In one clinical study, some subjects taking oral theanine reported drowsiness (96331).

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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).

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General ...Magnesium is generally well tolerated. Some clinical research shows no differences in adverse effects between placebo and magnesium groups.
Most Common Adverse Effects:
Orally: Diarrhea, gastrointestinal irritation, nausea, and vomiting.
Intravenously: Bradycardia, dizziness, flushing sensation, hypotension, and localized pain and irritation. In pregnancy, may cause blurry vision, dizziness, lethargy, nausea, nystagmus, and perception of warmth.
Serious Adverse Effects (Rare):
All ROAs: With toxic doses, loss of reflexes and respiratory depression can occur. High doses in pregnancy can increase risk of neonatal mortality and neurological defects.

Cardiovascular ...Intravenously, magnesium can cause bradycardia, tachycardia, and hypotension (13356,60795,60838,60872,60960,60973,60982,61001,61031,114681). Inhaled magnesium administered by nebulizer may also cause hypotension (113466). Magnesium sulfate may cause rapid heartbeat when administered antenatally (60915,114681).
In one case report, a 99-year-old male who took oral magnesium oxide 3000 mg daily for chronic constipation was hospitalized with hypermagnesemia, hypotension, bradycardia, heart failure, cardiomegaly, second-degree sinoatrial block, and complete bundle branch block. The patient recovered after discontinuing the magnesium oxide (108966).

Dermatologic ...Intravenously, magnesium may cause flushing, sweating, and problems at the injection site (including burning pain) (60960,60982,111696,114681). In a case study, two patients who received intravenous magnesium sulfate for suppression of preterm labor developed a rapid and sudden onset of an urticarial eruption (a skin eruption of itching welts). The eruption cleared when magnesium sulfate was discontinued (61045). Orally, magnesium oxide may cause allergic skin rash, but this is rare. In one case report, a patient developed a rash after taking 600 mg magnesium oxide (Maglax) (98291).

Gastrointestinal ...Orally, magnesium can cause gastrointestinal irritation, nausea, vomiting, and diarrhea (1194,4891,10661,10663,18111,60951,61016,98290). In rare cases, taking magnesium orally might cause a bezoar, an indigestible mass of material which gets lodged in the gastrointestinal tract. In a case report, a 75-year-old female with advanced rectal cancer taking magnesium 1500 mg daily presented with nausea and anorexia from magnesium oxide bezoars in her stomach (99314). Magnesium can cause nausea, vomiting, or dry mouth when administered intravenously or by nebulization (60818,60960,60982,104400,113466,114681). Antenatal magnesium sulfate may also cause nausea and vomiting (60915,114681). Two case reports suggest that giving magnesium 50 grams orally for bowel preparation for colonoscopy in patients with colorectal cancer may lead to intestinal perforation and possibly death (90006).
Delayed meconium passage and obstruction have been reported rarely in neonates after intravenous magnesium sulfate was given to the mother during pregnancy (60818). In a retrospective study of 200 neonates born prematurely before 32 weeks of gestation, administration of prenatal IV magnesium sulfate, as a 4-gram loading dose and then 1-2 grams hourly, was not associated with the rate of meconium bowel obstruction when compared with neonates whose mothers had not received magnesium sulfate (108728).

Genitourinary ...Intravenously, magnesium sulfate may cause renal toxicity or acute urinary retention, although these events are rare (60818,61012). A case of slowed cervical dilation at delivery has been reported for a patient administered intravenous magnesium sulfate for eclampsia (12592). Intravenous magnesium might also cause solute diuresis. In a case report, a pregnant patient experienced polyuria and diuresis after having received intravenous magnesium sulfate in Ringer's lactate solution for preterm uterine contractions (98284).

Hematologic ...Intravenously, magnesium may cause increased blood loss at delivery when administered for eclampsia or pre-eclampsia (12592). However, research on the effect of intravenous magnesium on postpartum hemorrhage is mixed. Some research shows that it does not affect risk of postpartum hemorrhage (60982), while other research shows that intrapartum magnesium administration is associated with increased odds of postpartum hemorrhage, increased odds of uterine atony (a condition that increases the risk for postpartum hemorrhage) and increased need for red blood cell transfusions (97489).

Musculoskeletal ...Intravenously, magnesium may cause decreased skeletal muscle tone, muscle weakness, or hypocalcemic tetany (60818,60960,60973).
Although magnesium is important for normal bone structure and maintenance (272), there is concern that very high doses of magnesium may be detrimental. In a case series of 9 patients receiving long-term tocolysis for 11-97 days, resulting in cumulative magnesium sulfate doses of 168-3756 grams, a lower bone mass was noted in 4 cases receiving doses above 1000 grams. There was one case of pregnancy- and lactation-associated osteoporosis and one fracture (108731). The validity and clinical significance of this data is unclear.

Neurologic/CNS ...Intravenously, magnesium may cause slurred speech, dizziness, drowsiness, confusion, or headaches (60818,60960,114681). With toxic doses, loss of reflexes, neurological defects, drowsiness, confusion, and coma can occur (8095,12589,12590).
A case report describes cerebral cortical and subcortical edema consistent with posterior reversible encephalopathy syndrome (PRES), eclampsia, somnolence, seizures, absent deep tendon reflexes, hard to control hypertension, acute renal failure and hypermagnesemia (serum level 11.5 mg/dL), after treatment with intravenous magnesium sulfate for preeclampsia in a 24-year-old primigravida at 39 weeks gestation with a previously uncomplicated pregnancy. The symptoms resolved after 4 days of symptomatic treatment in an intensive care unit, and emergency cesarian delivery of a healthy infant (112785).

Ocular/Otic ...Intravenously, magnesium may cause blurred vision (114681). Additionally, cases of visual impairment or nystagmus have been reported following magnesium supplementation, but these events are rare (18111,60818).

Psychiatric ...A case of delirium due to hypermagnesemia has been reported for a patient receiving intravenous magnesium sulfate for pre-eclampsia (60780).

Pulmonary/Respiratory ...Intravenously, magnesium may cause respiratory depression and tachypnea when used in toxic doses (12589,61028,61180).

Other ...Hypothermia from magnesium used as a tocolytic has been reported (60818).

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General ...Orally, L-theanine seems to be well tolerated.
Most Common Adverse Effects:
Orally: Drowsiness, headaches.

Neurologic/CNS ...Orally, L-theanine may cause headaches (36439). Patients have also reported drowsiness, increased duration of sleep, and increased dream activity after oral L-theanine use (96331).
A case of subtle facial tic starting within 4 days of taking L-theanine 400 mg daily has been reported for a pediatric patient. Although the tics reportedly ceased once theanine was discontinued, the child had exhibited tics in the past. Therefore, the adverse effect was not thought to be related to L-theanine (91744).

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