BioSom [Discontinued] by Metagenics

LIKELY EFFECTIVE

• Vaginal atrophy. Intravaginal DHEA can reduce pain during intercourse and improve vaginal health in patients with this condition. Details: Clinical research shows that ovules or suppositories containing DHEA 0.25% to 1%, inserted vaginally once daily for 12 weeks, can reverse vaginal thinning, restore vaginal pH, and reduce pain during sexual intercourse by up to 15% when compared with placebo in patients with vaginal atrophy (21320,21429,21430,94576). A specific vaginal insert containing DHEA 0.5% (Intrarosa, Endoceutics Inc.) is an FDA approved drug used for reducing pain during sexual intercourse in patients with vaginal atrophy (94573,94576). Other clinical research shows that applying DHEA 10% cream (Diosynth) to the inner thighs daily for 12 months might improve vaginal atrophy by stimulating maturation of the vaginal epithelium in postmenopausal patients. It might also increase bone mineral density in these patients (4242).

POSSIBLY EFFECTIVE

• Aging skin. Oral and topical DHEA have been evaluated for treating aging skin, with promising results. Details: Some clinical research shows that taking DHEA 50 mg daily for 12 months increases epidermal thickness, sebum production, and skin hydration, and decreases facial skin pigmentation in elderly patients (6446). Other preliminary clinical research shows that applying 1% DHEA daily for 4 months improves the appearance of paper-like skin when compared with placebo in postmenopausal patients. It also improves sebum production, skin wrinkling, and skin appearance when compared with baseline (21428).
• Depression. Oral DHEA 30-500 mg daily for up to 8 weeks seems to improve symptoms of depression and dysthymia in patients with depression. Details: Canadian clinical practice guidelines recommend DHEA as a third-line treatment for depression (95691). Most clinical research shows that taking DHEA 30-500 mg daily for around 6-8 weeks improves symptoms of depression and dysthymia when compared with placebo (3270,3864,3892,4233,21404,21405). Additionally, a pooled analysis of these and 9 other clinical studies shows that DHEA can improve depressive symptoms when compared with placebo, although most of the trials evaluated in the analysis included patients without clinically diagnosed depression (104161). Other preliminary clinical research using lower doses of 5-20 mg daily over 3 weeks shows no improvement in depressive symptoms in psychotic patients (21406).
• Infertility. Oral DHEA appears to improve fertility outcomes, including pregnancy and live birth rates, in females undergoing assisted reproduction. However, it is unclear if oral DHEA can reduce the risk for miscarriage after in vitro fertilization (IVF) or intra-cytoplasmic sperm injection (ICSI). Details: Meta-analyses of clinical research show that taking DHEA, typically at a dose of 75 mg daily, improves fertility outcomes for females undergoing assisted reproduction (96819,96820,96821,111227). One meta-analysis limited to randomized controlled trials in patients considered poor responders to standard IVF found that taking DHEA prior to IVF or ICSI treatments increases the clinical pregnancy rate by 34% and the rate of live births or ongoing pregnancy by 88% when compared with placebo or no treatment (96820). Another meta-analysis consisting of 16 studies, including both randomized controlled trials and observational research, in patients with diminished ovarian reserve (DOR) or poor ovarian response (POR) undergoing IVF or ICSI shows that taking DHEA 50-90 mg daily is associated with increases in oocyte yields, fertilized oocytes, top-quality embryos, clinical pregnancy rates, and ongoing pregnancy rates when compared with control groups. However, DHEA supplementation was not linked to improvements in live birth rates (111227). In females with various conditions of compromised fertility, some preliminary clinical research shows that taking DHEA 50-75 mg daily for at least 4 months may aid with natural conception, insemination-induced conception, and IVF pregnancy outcomes (21362). Some observational research in older females with DOR has also found that taking DHEA 30 mg three times daily for 12 weeks before IVF cycles is associated with a greater number of retrieved oocytes, improved oocyte quality, and increased cumulative pregnancy rates (103185). Inclusion of lower quality research also supports these findings (21413,21414,88493,96819,96821,99923). However, other research conflicts with findings that show a benefit of DHEA for infertility. (21415,88726,90304,111226). A large clinical study shows that pretreatment with DHEA in infertile females with POR prior to IVF and embryo transfer does not improve the number of retrieved oocytes and the rates of clinical pregnancy, pregnancy loss, and cumulative live births when compared with placebo (111226). Observational research in older patients with DOR suggests that DHEA supplementation is not linked to improved clinical pregnancy or live birth rates when compared with a control group (103185). Other clinical research in females with primary ovarian insufficiency shows that taking DHEA 75 mg daily for 16 weeks might not improve follicle size when compared with placebo (21364). The effect of DHEA pretreatment on miscarriage rates after IVF or ICSI is not clear. A meta-analysis of randomized clinical research does not support the use of DHEA pretreatment for preventing miscarriage (96820). However, when lower quality research is considered, use of DHEA seems to reduce the risk of miscarriage by up to 50% (21418,96819).

POSSIBLY INEFFECTIVE

• Aging. Oral DHEA, taken for up to 2 years, does not appear to improve bone health, quality of life, or sexual function in older adults. Details: Clinical research shows that DHEA, taken as 75 mg daily in males or 50 mg daily in females, for 2 years does not seem to improve body composition, bone mineral density (BMD), insulin sensitivity, or quality of life in people aged 60 years or older who have low DHEA-S levels (15027). Additionally, a pooled analysis of clinical trials shows that taking DHEA 50-1600 mg daily for up to 2 years does not improve body composition, bone health, sexual function, lipid and glycemic parameters, or quality of life in elderly males (88434).
• Muscle strength. Oral DHEA does not seem to improve muscle strength in adults. Details: While some clinical research shows that adults who take DHEA have increased muscle strength when measured by grip strength, leg press, chest press, and other measures, most clinical evidence shows that DHEA provides no benefit to muscle strength in younger and older adults (1365,10406,17617,21392,21419,21420,21421,47198).
• Physical performance. Oral DHEA does not seem to improve physical performance in elderly patients. Details: Most clinical research and a meta-analysis show that older adults who take DHEA do not have increased physical function or performance as measured by oxygen uptake, duration of exercise, balance, and ability to rise from a chair (17617,21420,21421). However, one clinical study shows that taking DHEA 50 mg daily for 6 months improves lower body strength and function by a small amount when compared with placebo in elderly frail females (21392). More research is needed to determine if DHEA is beneficial in specific populations.

LIKELY INEFFECTIVE

• Cognitive function. Oral DHEA does not improve cognitive function or prevent cognitive decline in most populations. Details: In the majority of clinical research, taking DHEA orally does not seem to improve cognitive function or decrease cognitive decline in healthy people over the age of 50 (3893,11334,14862,21333,21445), in peri- or post-menopausal women (6011,21397,21445), in patients with HIV (47435), or in young healthy adults when given as an acute dose (21399). However, preliminary clinical research shows that taking DHEA 50 mg daily for 4 weeks may improve certain measures of visual spatial performance and memory when compared with placebo in middle aged and elderly females (21396,21398).
• Sjogren syndrome. Oral DHEA does not appear to improve symptoms with this condition. Details: Clinical research shows that taking DHEA 50-200 mg daily for 4-12 months does not benefit symptoms of primary Sjogren syndrome when compared with placebo (21354,21358,21363,21365).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Addison disease. It is unclear if oral DHEA is beneficial in patients with this condition. Details: Some preliminary clinical research shows that taking DHEA up to 50 mg daily for up to 12 months improves symptoms of Addison disease, including reversing the loss of bone mineral density (BMD) and lean mass, but without improving cognitive function (8595,21387). However, taking DHEA 50 mg daily for 12 weeks does not appear to improve cognitive or sexual function, body composition, or BMD, although it may improve mood and fatigue (7614,21330,21356).
• Adrenal insufficiency. It is unclear if oral DHEA is beneficial in patients with primary or secondary adrenal insufficiency. Details: Some clinical research shows that taking low-dose DHEA, 20-50 mg daily, improves feelings of well-being, skin and hair, pubic hair growth, and sexuality in females with adrenal insufficiency or androgen deficiency due to hypopituitarism (3231,8593,17218,21317,21370,21385). However, other clinical research shows that taking low-dose DHEA for 3-12 months has little to no effect on quality of life, body composition, physical performance, cardiac function, depression, anxiety, and sexual arousal in patients with primary or secondary adrenal insufficiency (17218,21351,21357,21360,21386,21388,21389). Also, there is contradictory evidence about the effects of DHEA on plasma lipid levels in patients with adrenal insufficiency (21348,21351).
• Athletic performance. It is unclear if oral DHEA can improve sprint performance. Details: Preliminary clinical research in female recreationally trained athletes shows that taking DHEA 100 mg daily for 4 weeks does not improve sprint performance when compared with placebo (99925).
• Cardiovascular disease (CVD). Observational research has found that low DHEA levels are linked to a greater risk for CVD, but it is unclear if supplementation with oral DHEA is beneficial. Details: A meta-analysis of population research shows that patients with CVD and lower blood levels of DHEA-S have a worse overall prognosis when compared with patients with higher levels. Patients with the lowest levels have a 47% increased risk of future mortality events, including a 58% increased risk of fatal cardiovascular events. There was also a 42% increased risk of nonfatal cardiovascular events (96817). In elderly males, population research also shows that low serum levels of DHEA and DHEA-S are associated with an increased risk of coronary heart disease (CHD) but not cerebrovascular disease (90303).
• Cervical dysplasia. It is unclear if intravaginal DHEA is beneficial in patients with cervical dysplasia. Details: Preliminary clinical research shows that DHEA 150 mg intravaginally for up to 6 months reverses dysplasia in 83% of treated females with low-grade cervical dysplasia when compared to baseline (21426). The validity of these findings is limited by the lack of a comparator group.
• Chronic fatigue syndrome (CFS). It is unclear if oral DHEA is beneficial in patients with CFS. Details: Preliminary clinical research shows that oral DHEA 25-100 mg daily for 6 months improves symptoms of CFS by 8.5% to 26% when compared to baseline (7559). The validity of these findings is limited by the lack of a comparator group.
• Chronic obstructive pulmonary disease (COPD). It is unclear if oral DHEA is beneficial in patients with COPD. Details: A small clinical study shows that taking DHEA 200 mg daily for 3 months increases walking distance and improves lung function in patients with COPD when compared to baseline (21395). The validity of these findings is limited by the lack of a comparator group.
• Cocaine dependence. It is unclear if oral DHEA is beneficial for reducing cocaine cravings. Details: A small clinical study shows that taking DHEA 100 mg daily for 12 weeks, in addition to cognitive-behavioral group counseling, does not reduce cocaine craving when compared with counseling alone in cocaine-dependent participants (21411).
• Crohn disease. It is unclear if oral DHEA is beneficial for inducing Crohn disease remission. Details: A small clinical study shows that taking DHEA 200 mg daily for 8 weeks reduces symptoms in some patients with Crohn disease when compared to baseline. Remission occurred in 6 of 7 Crohn patients (21416). The validity of these findings is limited by the small study size and lack of a comparator group.
• Diabetes. Although there has been interest in using oral DHEA for diabetes, there is insufficient reliable information available about the clinical effects of DHEA for this purpose.
• Erectile dysfunction (ED). It is unclear if oral DHEA is beneficial in patients with ED. Details: Preliminary clinical research shows that taking DHEA orally for 24 weeks improves erectile function, orgasmic function, sexual desire, and overall sexual satisfaction in patients with ED. DHEA seems to be beneficial for idiopathic ED or ED secondary to hypertension, but doesn't seem to provide benefit for ED related to diabetes or neurological disorders (793,8596).
• Exercise-induced muscle damage. It is unclear if oral DHEA is beneficial for reducing muscle damage from exercise. Details: Preliminary clinical research shows that taking DHEA 50 mg twice daily for 5 days improves delayed-onset muscle soreness and reduces post-training blood creatinine kinase levels when compared with placebo in young males completing a 5-day exercise training program (88375).
• Fibromyalgia. It is unclear if oral DHEA is beneficial for improving fibromyalgia symptoms. Details: Preliminary clinical research shows that taking DHEA 50 mg daily for 3 months does not reduce fibromyalgia symptoms when compared with placebo in postmenopausal patients with fibromyalgia (21355).
• HIV/AIDS. Small clinical studies suggest that oral DHEA may improve mental health and quality of life in patients with HIV/AIDS, but DHEA does not seem to improve CD4 counts or body composition. Details: Population research shows that levels of DHEA seem to be lower in patients with more severe HIV/AIDS, suggesting that DHEA could be a marker for disease severity. Some evidence suggests that lower DHEA levels are associated with an increased risk of disease progression and AIDS (8598,14278,14279). Some clinical research shows that taking DHEA 50-500 mg daily for 2-4 months might improve mental health and quality of life when compared with placebo (3864,8598,14277,21390). However, taking DHEA in doses up to 2.25 grams daily does not appear to improve CD4 counts, muscle mass, or bone mass when compared with placebo (3865,14277,21390).
• Menopausal symptoms. Oral DHEA might reduce hot flashes and intravaginal DHEA might improve vaginal atrophy and sexual activity; however, oral DHEA does not seem to improve psychological symptoms associated with menopause. Details: Some research shows that taking DHEA 10-25 mg daily for 12 months improves subjective vasomotor symptoms such as hot flashes, as well as psychological symptoms and sexuality (11464,21417). Also, administering a daily ovule containing DHEA (Vaginorm, Recipharm) 3.5-13 mg intravaginally for 12 weeks appears to reverse vaginal atrophy and improve sexual activity in postmenopausal patients with vaginal atrophy (21442). However, other clinical research shows that taking DHEA 50 mg daily for up to 26 weeks does not improve mood, fatigue, cognition, sexual function, or sense of well-being in post- or peri-menopausal patients when compared with placebo (6011,21361). Additionally, a pooled analysis of clinical research shows that DHEA taken orally does not improve psychological symptoms related to menopause (88492).
• Metabolic syndrome. It is unclear if oral DHEA is beneficial for reducing risk for metabolic syndrome. Details: Preliminary clinical research shows that taking DHEA 50 mg daily for 6 months or 100 mg daily for 3 months decreases weight, abdominal fat, and blood pressure and reduces cholesterol, glucose, and insulin levels when compared with placebo in overweight elderly patients (12215,21350).
• Muscular dystrophy. It is unclear if oral DHEA is beneficial in patients with myotonic dystrophy type I. Details: Taking DHEA 100 or 400 mg daily for 12 weeks might not affect muscle strength in patients with myotonic dystrophy type I when compared with placebo (21334). However, intravenous DHEA-S 200 mg daily for 8 weeks appears to improve daily function, muscle strength, and heart function compared with baseline (21434). The validity of this finding is limited by the lack of a control group.
• Obesity. It is unclear if oral DHEA is beneficial for reducing body weight in patients who are obese or overweight. Details: Preliminary clinical research shows that taking DHEA 40 mg sublingually twice daily for 8 weeks, or 1600 mg by mouth for 28 days, does not affect body weight or body composition when compared with placebo in obese adults (21410,21427). Also, preliminary clinical research shows that taking DHEA 50-100 mg daily for 3-12 months does not affect central adiposity in older individuals when compared with placebo (21349).
• Opioid withdrawal. It is unclear if oral DHEA is beneficial in patients with heroin withdrawal. Details: Preliminary clinical research shows that taking DHEA 100 mg daily as adjunct to standard therapy for 12 months does not improve drug withdrawal symptoms in heroin addicts when compared with standard therapy alone (21412).
• Osteoporosis. It is unclear if oral DHEA is beneficial in patients with osteoporosis; any benefit may depend on individual patient characteristics. Details: There is contradictory evidence about the effectiveness of DHEA 50-100 mg daily for improved bone mineral density (BMD) in older adults with osteoporosis or osteopenia (12563,12564,21392), as well as the effectiveness of DHEA for improved BMD in females with anorexia nervosa (12562,21393). One pooled analysis shows that DHEA does not improve BMD in postmenopausal patients (88492), while another shows that DHEA can increase hip BMD in healthy older females, but not males (103186). The reason for these discrepant findings is unclear, but may relate to different patient populations, durations of therapy, and DHEA doses assessed in the included studies. Additionally, most of the studies included in these analyses were of low quality and inadequate statistical power.
• Parkinson disease. Although there has been interest in using oral DHEA for Parkinson disease, there is insufficient reliable information available about the clinical effects of DHEA for this purpose.
• Partial androgen deficiency. It is unclear if oral DHEA is beneficial for symptom improvement in patients with this condition. Details: Preliminary clinical research shows that taking DHEA 25 mg daily for one year might clinically improve mood, fatigue, and joint pain in older males with partial androgen deficiency when compared to baseline (21331). Other preliminary clinical research shows that taking DHEA 50 mg twice daily for 4 months does not improve erectile or sexual function when compared with placebo in hypoandrogenic males (21424).
• Parturition. Intravenous DHEA before the onset of labor may shorten the time to labor onset and shorten labor duration. Details: Clinical research shows that intravenous DHEA-S 100 mg daily for 3 days, or given twice weekly until the onset of labor starting after 38 weeks of gestation, increases cervical ripening and shortens the time to onset of labor and the duration of labor when compared with a control in nulliparous women (21384,21431). Also, intravenous DHEA 50-200 mg given multiple times until the onset of labor starting after 37 weeks of gestation appears to shorten the time to delivery in primiparous and multiparous women (21432,21433). It is unclear if oral DHEA is beneficial for this purpose.
• Rheumatoid arthritis (RA). It is unclear if oral DHEA is beneficial in patients with RA. Details: Preliminary clinical research shows that taking oral DHEA 200 mg for 16 weeks does not reduce symptoms of RA in elderly patients (21422). However, other clinical research in a small number of premenopausal females with RA shows that taking DHEA 50 mg daily for 12 weeks improves quality of life, but not disease activity, when compared with placebo (104159).
• Schizophrenia. It is unclear if oral DHEA is beneficial in patients with schizophrenia. Details: Some research shows that taking DHEA orally improves both negative and positive symptoms in patients with schizophrenia. It may be more effective in females (9692). However, other clinical research shows no benefit (21423).
• Sexual dysfunction. It is unclear if oral or intravaginal DHEA is beneficial for improving sexual dysfunction in males or females. Details: DHEA may be modestly beneficial in some postmenopausal patients with decreased libido or dyspareunia. Preliminary clinical research shows that taking DHEA 50-100 mg daily, or a single dose of DHEA 300 mg, improves sexual desire when compared to baseline (9906,21443). Additional clinical research shows that use of intravaginal DHEA (Vaginorm, Recipharm) at concentrations of 0.25% to 1% daily for 12 weeks might improve sexual function when compared with placebo (47361). However, a pooled analysis shows that DHEA is not associated with improvements in libido or sexual function (88414,88492). DHEA has also been evaluated in other patient populations. Small clinical studies show that taking DHEA doesn't seem to influence response to sexual stimuli in sexually functional premenopausal women (8594) or improve libido in individuals age 40-70 years (21449). Preliminary clinical research in males with hypoactive sexual desire disorder (HSDD) shows that taking DHEA 50 mg twice daily for 6 weeks does not improve erectile or sexual function when compared with placebo (88414). In adults with midlife-onset or HIV-associated depression, preliminary clinical research shows that taking DHEA 90-500 mg daily for 3-8 weeks may improve sexual function and libido when compared with placebo (3864,21405).
• Systemic lupus erythematosus (SLE). Most small clinical studies suggest that oral DHEA may modestly improve symptoms in patients with SLE, but some conflicting research exists. Details: Some clinical research shows that taking DHEA has little to no effect on disease activity in patients with mild to moderate SLE (21425,21447). However, small clinical studies and a meta-analysis of these studies show that taking DHEA in conjunction with conventional treatment may help improve frequency of flare-ups, muscle ache, oral ulcers, and quality of life, reduce corticosteroid doses needed (2113,2114,2136,6068,6447,12561,12574,21346,21447), and improve bone mineral density (6068,6097,6447,21394).
• Ulcerative colitis. It is unclear if oral DHEA is beneficial for inducing ulcerative colitis remission. Details: A small clinical study shows that taking DHEA 200 mg daily for 8 weeks reduces symptoms of ulcerative colitis when compared to baseline in some patients with ulcerative colitis. Remission occurred in 6 of 13 ulcerative colitis patients (21416). The validity of these findings is limited by the small study size and the lack of a comparator group. More evidence is needed to rate DHEA for these uses.

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INSUFFICIENT RELIABLE EVIDENCE to RATE

• Acne. Although there has been interest in using topical grapefruit oil for acne, there is insufficient reliable information about the clinical effects of grapefruit for this purpose.
• Asthma. It is unclear if oral grapefruit is beneficial in patients with asthma. Details: There is some evidence that consumption of vitamin C-rich citrus fruits, including grapefruit and others, might improve lung function in people with asthma. Intake of citrus fruits 1-2 times weekly has produced this benefit in some studies (6049,6055,6056). However, other studies have shown no benefit (6057,6058).
• Atherosclerosis. Although there has been interest in using oral grapefruit to treat or prevent atherosclerosis, there is insufficient reliable information about the clinical effects of grapefruit for this purpose.
• Atopic dermatitis (eczema). It is unclear if oral grapefruit seed extract is beneficial in patients with atopic dermatitis. Details: One small, uncontrolled clinical study in patients with atopic dermatitis shows that taking a specific grapefruit seed extract product (ParaMicrocidin, Allergy Research Group) 150 mg three times daily for one month can decrease complaints of constipation, flatulence, and abdominal discomfort, possibly due to changes in intestinal microflora (5866). The validity of these findings is limited by a lack of control group.
• Depression. Although there has been interest in using inhaled grapefruit oil as aromatherapy for depression, there is insufficient reliable information about the clinical effects of grapefruit oil for this purpose.
• Gingivitis. Although there has been interest in using topical grapefruit oil as a rinse for gingivitis, there is insufficient reliable information about the clinical effects of grapefruit oil for this purpose.
• Headache. Although there has been interest in using inhaled grapefruit oil as aromatherapy for headache, there is insufficient reliable information about the clinical effects of grapefruit oil for this purpose.
• Hypercholesterolemia. It is unclear if oral grapefruit is beneficial in patients with hypercholesterolemia. Details: One small clinical study in patients with hypercholesterolemia shows that taking capsules containing grapefruit pectin 5 grams three times daily for 16 weeks decreases total cholesterol by 8% and the ratio of low-density lipoprotein (LDL) to high-density lipoprotein (HDL) cholesterol by 10% when compared to baseline (2216). The validity of these findings is limited by the lack of a comparator group.
• Hypertriglyceridemia. It is unclear if oral grapefruit is beneficial in patients with hypertriglyceridemia. Details: One small clinical study in patients with hypertriglyceridemia that is not well controlled on statin therapy shows that consuming one red or white grapefruit daily for 30 days reduces total cholesterol by 8% to 15.5% and low-density lipoprotein (LDL) cholesterol by 11% to 20% when compared with placebo. In addition, consuming one red, but not one white, grapefruit daily reduces triglyceride levels by 17% when compared with placebo in these patients (53352).
• Intestinal parasite infection. Although there has been interest in using oral grapefruit seed extract for intestinal parasite infections, there is insufficient reliable information about the clinical effects of grapefruit for this purpose.
• Lice. It is unclear if topical grapefruit extract is beneficial in children with head lice. Details: One small clinical study in children aged 2-9 years with head lice shows that applying 50 mL of a specific shampoo containing grapefruit extract (Licatack shampoo) to the hair for 10-20 minutes and then rinsing with water and combing can eliminate adult lice. Applying a second application after 10 days seems to help remove any remaining nits (91417). The validity of these findings is limited by a lack of control group.
• Obesity. While some small studies suggest that oral grapefruit extract, taken in combination with other citrus extracts, may modestly improve weight loss, the effect of oral grapefruit alone is unclear. Details: One small clinical study in obese adults shows that consuming one and a half fresh grapefruits daily for 12 weeks reduces body weight by 1.3 kg when compared with placebo. Also, although drinking 8 ounces of grapefruit juice or taking grapefruit capsules three times daily for 12 weeks did not improve body weight when compared with placebo in the overall study population, a sub-group analysis of obese adults with metabolic syndrome shows that taking grapefruit capsules or drinking grapefruit juice increases weight loss and improves insulin resistance when compared with placebo (53353). Grapefruit has also been evaluated in combination with other citrus ingredients. Two clinical studies shows that taking a specific combination product (Sinetrol, Fytexia) containing sweet orange, blood orange, and grapefruit extracts for 12 weeks can decrease body weight, body fat percentage, and body mass index (BMI) in otherwise healthy overweight adults (95517,95518). In one study, taking this supplement as 450 mg twice daily for 12 weeks reduced body weight by 1 kg and body fat percentage by 6.5% when compared with placebo. Hip circumference, waist circumference, and blood glucose were also reduced when compared with placebo (95518). In another study, taking this same supplement as 700 mg twice daily for 12 weeks reduced body weight by 5.6 kg, body fat percentage by 5%, and BMI by 2% when compared to baseline. Patients taking placebo experienced no significant improvements from baseline (95517). It is not clear if these effects are due to grapefruit extract, other ingredients, or the combination.
• Pharyngitis. Although there has been interest in using topical grapefruit oil as a gargle for pharyngitis, there is insufficient reliable information about the clinical effects of grapefruit oil for this purpose.
• Psoriasis. Although there has been interest in using oral grapefruit for psoriasis, there is insufficient reliable information about the clinical effects of grapefruit for this purpose.
• Stress. Although there has been interest in using inhaled grapefruit oil as aromatherapy for stress, there is insufficient reliable information about the clinical effects of grapefruit oil for this purpose.
• Upper respiratory tract infection (URTI). Although there has been interest in using grapefruit oil as aromatherapy for various upper respiratory tract infections, including influenza and the common cold, there is insufficient reliable information about the clinical effects of grapefruit oil for these conditions.
• Vaginal candidiasis. Although there has been interest in using oral and topical grapefruit seed extract for vaginal candidiasis, there is insufficient reliable information about the clinical effects of grapefruit seed extract for this purpose. More evidence is needed to rate grapefruit for these uses.

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INSUFFICIENT RELIABLE EVIDENCE to RATE

• Diabetes. It is unclear if oral stevia is beneficial in patients with diabetes; the available research is conflicting. Details: A small single-dose study shows that taking stevia leaf extract 1000 mg, standardized to contain 91% stevioside, along with a meal reduces postprandial glucose levels by 18% in adults with type 2 diabetes when compared with a starch control (11812). However, clinical research in patients with type 1 or type 2 diabetes shows that taking stevioside 250 mg three times daily for 3 months does not affect blood glucose levels or glycated hemoglobin (HbA1C) when compared with baseline (16705). Also, a small clinical study in patients with diabetes shows that drinking 200 mL of black tea, sweetened with stevia extract 2%, three times daily for 8 weeks does not affect glycemic indices when compared with drinking tea sweetened with sucralose (103695).
• Hypertension. It is unclear if oral stevia is beneficial in patients with hypertension; the available research is conflicting. Details: Some clinical research in patients with mild to moderate hypertension shows that taking stevioside, a constituent of stevia, 750-1500 mg in three divided doses daily reduces systolic blood pressure by 10-14 mmHg and diastolic blood pressure by 6-14 mmHg within one week to three months of treatment initiation and continuing for up to 2 years (11809,11810). However, other clinical research in patients with mild hypertension shows that taking stevioside in doses up to 15 mg/kg daily does not significantly reduce blood pressure (16706).
• Obesity. It is unclear if oral stevia is beneficial in patients with obesity; the available research is conflicting. Details: Although a small clinical study in healthy adults shows that drinking water with stevia (Truvia) 245 ppm as a single dose reduces appetite and energy intake when compared with drinking water alone (103697), other small, single-dose studies have shown no effect of stevia 15.3 mg or 1 gram as a single dose on satiety, energy intake, or fullness when compared with either water alone or a non-nutritive sweetener (103696,110124). A small clinical study in healthy adults shows that taking an aqueous stevia leaf extract (SweetLeaf) twice daily for 12 weeks does not affect body weight, compared with an increase in weight in the control group. This suggests that stevia extract may have attenuated weight gain in this study (106458). More evidence is needed to rate stevia for these uses.

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POSSIBLY SAFE ...when used orally and appropriately, short-term. Most studies have been small and lasted from a few weeks to 6 months, with usual doses of 50 mg daily (793,1635,2133,3231,4249,4251,4252,4253,4254,4255,9691)(9692,10986,12215,12564,14277,21416,88726,90304,99925). Some studies have also used oral DHEA with apparent safety for 12-24 months (2113,6446,10406,11464,12561,15027,88492). ...when used intravaginally and appropriately. Intravaginal ovules of DHEA 3.25 mg to 13 mg have been safely used for up to 12 weeks (21320,21429,21430). ...when used topically and appropriately. A DHEA cream 1% to 10% has been safely used for up to 12 months (4242,21428).

POSSIBLY UNSAFE ...when used orally in high doses or long-term. There is concern that long-term use or use of amounts that cause higher than normal physiological DHEA levels might increase the risk of prostate cancer (2111,12565), breast cancer (10370,10401,10403), or other hormone-sensitive cancers (6445). In some cases, 50-100 mg daily can produce slightly higher than normal physiological DHEA levels (4249,4251). There is insufficient reliable information available about the safety of using DHEA intravenously or intramuscularly.

PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally. DHEA can cause higher than normal androgen levels (2133,4249,4251,4253), which might adversely affect pregnancy or a nursing infant.

(Read more about DHEA)

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

POSSIBLY SAFE ...when used orally and appropriately for medicinal purposes. A grapefruit seed extract has been safely used in clinical research (5866). In addition, capsules containing grapefruit pectin 15 grams daily have been used in clinical research for up to 16 weeks (2216).

POSSIBLY UNSAFE ...when used orally in excessive amounts. Preliminary population research shows that consuming a quarter or more of a whole grapefruit daily is associated with a 25% to 30% increased risk of postmenopausal breast cancer (14858). Grapefruit juice is thought to reduce estrogen metabolism resulting in increased endogenous estrogen levels. More evidence is needed to validate this finding.

PREGNANCY AND LACTATION:
There is insufficient reliable information available about the safety of using medicinal amounts of grapefruit during pregnancy and lactation; avoid using.

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LIKELY SAFE ...when certain stevia constituents, including stevioside and rebaudiosides A, D, and M, are used orally as sweeteners in foods. These constituents have generally recognized as safe (GRAS) status in the US for this purpose (16699,16700,16702,16705,16706,108049). The stevia constituent stevioside has been safely used in doses of up to 1500 mg daily for 2 years (11809,11810,11811). There is insufficient reliable information available about the safety of whole stevia or stevia extracts when used orally. The European Food Safety Authority (EFSA) has determined that the acceptable intake of steviol glycosides is 4 mg/kg daily (106456); however, it is unclear how this relates to the use of whole stevia or stevia extract.

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

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details Human and laboratory research show that DHEA and DHEA-S can inhibit platelet aggregation (19109,19127).

ANTIDEPRESSANT DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might increase the risk of psychiatric adverse events when used with antidepressants.  Details In a human case report, the use of a selective serotonin reuptake inhibitor (SSRI) with DHEA caused a manic episode (7023). Concern for this interaction may be greater in younger individuals with higher baseline DHEA levels.

AROMATASE INHIBITORS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might interfere with the clinical effects of aromatase inhibitors.  Details DHEA is a potent estrogen agonist, which may antagonize the anti-estrogen activity of aromatase inhibitors (10401).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might increase the levels of drugs metabolized by CYP3A4.  Details Some preliminary evidence shows that DHEA may inhibit CYP3A4 (1389); however, the clinical significance of this potential interaction is not known.

ESTROGENS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might increase the effects and adverse effects of estrogen therapy.  Details DHEA is a precursor to estrogen and androgen and is metabolized into those substances. In clinical research, DHEA supplements increase the levels of these hormones (6012,7614,8593,10986,12651,12564,15027,21321,21323,21324)(21325,21326,21327,21328,21330,21331,21356,21364,21389,21393)(21397,21398,21417,21419,21427,47273,47348,88375,90304). Also, in clinical research, estrogen-progestin oral contraceptives and conjugated estrogens reduce blood levels of DHEA and DHEA-S (21372,21373,21374,21437,21438). The clinical significance of these findings is unclear.

FULVESTRANT (Faslodex) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might interfere with the anti-estrogen effects of fulvestrant.  Details DHEA is a potent estrogen agonist (10401). Some research shows that it can overcome the estrogen receptor antagonist action of fulvestrant in estrogen-receptor positive cancer cells (10370).

TAMOXIFEN (Nolvadex) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might interfere with the anti-estrogen effects of tamoxifen.  Details DHEA is a potent estrogen agonist. Some research shows that it can overcome the estrogen receptor antagonist activity of tamoxifen in estrogen-receptor positive cancer cells (10370,10403).

TESTOSTERONE Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, DHEA might increase the effects and side effects of testosterone therapy.  Details DHEA is a precursor to estrogen and androgen and is metabolized into those substances. In clinical research, DHEA supplements increase the levels of these hormones (6012,7614,8593,10986,12651,12564,15027,21321,21323,21324)(21325,21326,21327,21328,21330,21331,21356,21364,21389,21393)(21397,21398,21417,21419,21427,47273,47348,88375,90304,99924,99925,104162). The clinical significance of these findings is unclear.

TRIAZOLAM (Halcion) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D DHEA can increase blood levels of triazolam.  Details Administration of DHEA 200 mg daily for two weeks was shown to inhibit the cytochrome P450 3A4 (CYP3A4) metabolism of triazolam. This inhibition appears to be due to DHEA-S, rather than DHEA (1389).

TUBERCULOSIS VACCINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D DHEA might reduce the effectiveness of the tuberculosis vaccine.  Details Animal research shows that high doses of DHEA can reduce the efficacy of the Bacillus Calmette-Guérin (BCG) tuberculosis vaccine (21316).

(Read more about DHEA)

ACEBUTOLOL (Sectral) Interaction Rating = Minor Be watchful with this combination. Severity = Insignificant •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can decrease blood levels of acebutolol, potentially decreasing the clinical effects of acebutolol.  Details Clinical research shows that grapefruit juice can modestly decrease acebutolol levels by 7% and reduce peak plasma concentration by 19% by inhibiting organic anion transporting polypeptide (OATP) (17603,18101). The acebutolol half-life is also extended by 1.1 hours when grapefruit juice is consumed concomitantly (18101). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

ALISKIREN (Tekturna, Rasilez) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can decrease blood levels of aliskiren, potentially decreasing the clinical effects of aliskiren.  Details Clinical research shows that grapefruit juice can decrease aliskiren levels by approximately 60% by inhibiting organic anion transporting polypeptide (OATP) (91428). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

AMIODARONE (Cordarone) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of amiodarone, potentially increasing the effects and adverse effects of amiodarone.  Details Clinical research shows that grapefruit juice inhibits metabolism and increases absorption of amiodarone. Grapefruit juice increases amiodarone plasma levels by 50% and peak concentration by 84% (17601,17672,22120).

AMPRENAVIR (Agenerase) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice might decrease blood levels of amprenavir, although this is not likely to be clinically significant.  Details Some clinical research shows that grapefruit juice can slightly decrease amprenavir levels (17673); however, this is probably not clinically significant.

ARTEMETHER (Artenam, Paluther) Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of oral artemether, potentially increasing the effects and adverse effects of artemether.  Details Clinical research shows that grapefruit juice increases the levels of oral artemether by 90% to 250% in healthy males (5065,5066).

BENZODIAZEPINES Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice might increase blood levels of some oral benzodiazepines, potentially increasing the effects and adverse effects of these drugs.  Details Clinical research shows that grapefruit juice can increase plasma triazolam concentrations. Repeated consumption of grapefruit juice greatly increases triazolam concentrations and prolongs the half-life, probably due to inhibition of cytochrome P450 3A4 (CYP3A4) (7776,22118,22131,22133). Some studies show that grapefruit juice, particularly when taken in large quantities, reduces the clearance and increases the maximum blood levels, area under the plasma concentration curve (AUC), and duration of effect of midazolam. However, there is no effect on intravenous midazolam (4300,10159,11275,17601,22117,22119,16711,91427,95978). Grapefruit juice has also been shown to increase the maximum blood levels and duration of effect of diazepam, but the clinical significance of this is not known (3228). This interaction does not appear to occur with alprazolam (17674).

BLONANSERIN (Lonasen) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of blonanserin, potentially increasing the effects and adverse effects of blonanserin.  Details Blonanserin is metabolized primarily by cytochrome P450 3A4 (CYP3A4). A small clinical study shows that taking grapefruit juice along with oral blonanserin increases exposure to blonanserin almost 6-fold due to inhibition of intestinal CYP3A4 by grapefruit juice and prolongs the elimination half-life of blonanserin by 2.2-fold due to inhibition of hepatic CYP3A4 by grapefruit juice (96943).

BUDESONIDE (Entocort, UCERIS) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of budesonide, potentially increasing the effects and adverse effects of budesonide.  Details Budesonide is metabolized by cytochrome P450 3A4 (CYP3A4). A small clinical study shows that taking grapefruit juice along with oral budesonide increases the plasma concentration of budesonide. This effect is attributed to grapefruit-induced inhibition of CYP3A4 in both the colon and small intestine (91425).

BUSPIRONE (BuSpar) Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of buspirone, potentially increasing the effects and adverse effects of buspirone.  Details Clinical research shows that grapefruit juice increases absorption and plasma concentrations of buspirone (3771).

CAFFEINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Grapefruit juice can decrease the clearance of caffeine, potentially increasing the effects and adverse effects of caffeine.  Details Clinical research shows that grapefruit juice decreases caffeine clearance (4300).

CALCIUM CHANNEL BLOCKERS Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of oral calcium channel blockers, potentially increasing the effects and adverse effects of these drugs.  Details Clinical research shows that grapefruit juice increases absorption and plasma concentrations of amlodipine (523), nifedipine (528,22114), nisoldipine (529), verapamil (7779,8285), felodipine, nimodipine, nicardipine, diltiazem, pranidipine, nitrendipine, and manidipine (524,528,1388,4300,7780,11276,22136,53338,22138,22139) (22140,22141,22142,22143,22147,22148,22149,53367,22158), This interaction is likely the result of the inhibition of intestinal metabolism of these drugs by CYP3A4 (7779,7780), although some research suggests grapefruit may alter plasma drug levels by reducing the rate of gastric emptying (22167). Consuming grapefruit juice 1 liter daily increases steady state concentrations of verapamil by as much as 50% (8285). However, some references dispute the clinical relevance of the interactions with amlodipine, diltiazem, and verapamil (3230,4300,22159). Other research in healthy individuals suggests plasma levels of felodipine and nifedipine are not affected when given intravenously (22144,22146). There is considerable interindividual variability in the effect of grapefruit juice on drug metabolism, which might account for inconsistent study results (7777,7779,8285). In healthy older adults, the hemodynamic response to felodipine plus grapefruit juice might be influenced by altered autonomic regulation. In older healthy adults, a single dose of grapefruit juice and felodipine enhanced the blood pressure-lowering effects of felodipine. However, after a week of grapefruit juice and felodipine (steady state), the hypotensive activity was reduced, possibly due to compensatory tachycardia (1392). Research indicates it is necessary to withhold grapefruit juice for as long as 3 days to avoid interactions with felodipine and nisoldipine (5068,5069,6453,22145).

CARBAMAZEPINE (Tegretol) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of carbamazepine, potentially increasing the effects and adverse effects of carbamazepine.  Details Clinical research shows that grapefruit juice increases absorption and plasma concentrations of carbamazepine (524).

CARVEDILOL (Coreg) Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of carvedilol, potentially increasing the effects and adverse effects of carvedilol.  Details Clinical research shows that grapefruit juice increases the bioavailability of a single dose of carvedilol by 16% (5071).

CELIPROLOL (Celicard) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of celiprolol, potentially decreasing the clinical effects of celiprolol.  Details In human research, taking grapefruit juice within two hours of celiprolol appears to decrease absorption and blood levels of celiprolol by approximately 85% (91421). This interaction is due to grapefruit-induced inhibition of organic anion transporting polypeptide (OATP) (17603,17604,22161). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

CISAPRIDE (Propulsid) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of cisapride, potentially increasing the effects and adverse effects of cisapride.  Details Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cisapride. According to the cisapride prescribing information, grapefruit juice is contraindicated in patients taking cisapride (1383,3226,17601,22164,22165).

CLOMIPRAMINE (Anafranil) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = D Theoretically, grapefruit juice might increase blood levels of clomipramine, potentially increasing the effects and adverse effects of clomipramine.  Details Case reports have shown that clomipramine trough levels increase significantly after the addition of grapefruit juice to the therapeutic regimen (5064).

CLOPIDOGREL (Plavix) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of the active metabolite of clopidogrel, thereby decreasing the antiplatelet effect of clopidogrel.  Details Clopidogrel is an antiplatelet prodrug that is metabolized primarily by cytochrome P450 2C19 (CYP2C19) to form the active metabolite. A small clinical study shows that taking grapefruit juice with clopidogrel decreases plasma levels of the active metabolite by more than 80% and impairs the antiplatelet effect of clopidogrel. This effect is possibly due to grapefruit-induced inhibition of CYP2C19 (91419).

COLCHICINE Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, grapefruit juice might increase blood levels of colchicine, potentially increasing the effects and adverse effects of colchicine.  Details Colchicine is an alkaloid that undergoes P-glycoprotein (P-gp) mediated drug efflux in the intestines, followed by metabolism by cytochrome P450 3A4 (CYP3A4). There is concern that grapefruit juice will increase the effects and adverse effects of colchicine due to grapefruit-induced inhibition of P-gp and/or CYP3A4. In vitro evidence shows that grapefruit juice increases absorption of colchicine by inhibiting P-gp (94158). A case of acute colchicine toxicity has been reported for an 8-year-old female who drank grapefruit juice while taking high-dose colchicine, long-term (94157). However, one small clinical study in healthy adults shows that drinking grapefruit juice 240 mL twice daily for 4 days does not affect the bioavailability or adverse effects of a single dose of colchicine 0.6 mg taken on the fourth day (35762).

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of oral cyclosporine, potentially increasing the effects and adverse effects of cyclosporine.  Details Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cyclosporine (522,11270,22113,22150,22152,22153,22154,22155). The mechanism of action is unclear. However, there is no effect on intravenous cyclosporine (22151).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP1A2.  Details In vitro research suggests that grapefruit juice might inhibit CYP1A2 enzymes (12479). So far, this interaction has not been reported in humans.

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP2C19.  Details In vitro research suggests that grapefruit juice might inhibit CYP2C19 enzymes (12479). Also, a small clinical study shows that taking grapefruit juice with clopidogrel, an antiplatelet prodrug that is metabolized primarily by CYP2C19, decreases plasma levels of the active metabolite and impairs the antiplatelet effect of clopidogrel. This effect is likely due to grapefruit-induced inhibition of CYP2C19 (91419).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP2C9.  Details In vitro research suggests that grapefruit juice might inhibit CYP2C9 enzymes (12479). So far, this interaction has not been reported in humans.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase levels of drugs metabolized by CYP3A4.  Details Clinical research shows that grapefruit juice can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects (3227,3774,8283,8285,8286,22129,91427,104190). When taken orally, effects of grapefruit juice on CYP3A4 levels appear to last at least 48 hours (91427). Grapefruit's ability to inhibit CYP3A4 has even been harnessed to intentionally increase levels of venetoclax, which is metabolized by CYP3A4, in an elderly patient with acute myeloid leukemia who could not afford full dose venetoclax. The lower dose of venetoclax in combination with grapefruit juice resulted in serum levels of venetoclax in the therapeutic reference range of full dose venetoclax and positive treatment outcomes for the patient (112287). Professional consensus recommends the consideration of patient age, existing medical conditions, additional medications, and the potential for additive adverse effects when evaluating the risks of concomitant use of grapefruit juice with any medication metabolized by CYP3A4. While all patients are at risk for interactions with grapefruit juice consumption, patients older than 70 years of age and those taking multiple medications are at the greatest risk for a serious or fatal interaction with grapefruit juice (95970,95972).

DAPOXETINE (Priligy) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of dapoxetine, potentially increasing the effects and adverse effects of dapoxetine.  Details Pharmacokinetic research shows that drinking grapefruit juice 250 mL prior to taking dapoxetine 60 mg can increase the maximum plasma concentration of dapoxetine by 80% and prolong the elimination half-life by 43%. This effect is attributed to the inhibition of both intestinal and hepatic cytochrome P450 3A4 (CYP3A4) by grapefruit (95975).

DEXTROMETHORPHAN (Robitussin DM, others) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of dextromethorphan, potentially increasing the effects and adverse effects of dextromethorphan.  Details Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism, causing increased dextromethorphan levels (11362).

ERYTHROMYCIN Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of erythromycin, potentially increasing the effects and adverse effects of erythromycin.  Details Clinical research shows that concomitant use of erythromycin with grapefruit can inhibit cytochrome P450 3A4 (CYP3A4) metabolism of erythromycin, increasing plasma concentrations of erythromycin by 35% (8286).

ESTROGENS Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of estrogens, potentially increasing the effects and adverse effects of estrogens.  Details Clinical research shows that grapefruit increases the levels of endogenous and exogenous estrogens by inhibiting cytochrome P450 3A4 (CYP3A4) enzymes (525,526,14858). Grapefruit juice increases exogenously administered 17-beta-estradiol by about 20% in females without ovaries and ethinyl-estradiol in healthy females (525,526,22160).

ETOPOSIDE (VePesid) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of etoposide, potentially decreasing the clinical effects of etoposide.  Details Clinical research shows that grapefruit juice decreases the absorption and plasma concentrations of etoposide. There is some evidence that grapefruit juice co-administered with oral etoposide can reduce levels of etoposide by about 26% (8744). Grapefruit juice seems to inhibit organic anion transporting polypeptide (OATP), which is a drug transporter in the gut, liver, and kidney (7046,17603,17604). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

FEXOFENADINE (Allegra) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can decrease blood levels of fexofenadine, thereby decreasing the clinical effects of fexofenadine.  Details Clinical research shows that grapefruit juice can significantly decrease oral absorption and blood levels of fexofenadine. In one study, consuming a drink containing grapefruit juice 25% decreased bioavailability of fexofenadine by about 24%. Consuming a full-strength grapefruit juice drink reduced bioavailability by 67% (7046). In another study, consuming grapefruit juice 300 mL decreased fexofenadine levels by 42%. Consuming 1200 mL of grapefruit juice reduced levels by 64% (17602). Similarly, drinking grapefruit juice 240 mL decreased the oral bioavailability of fexofenadine by 25% in another pharmacokinetic study (112288). Fexofenadine manufacturer data indicates that concomitant administration of grapefruit juice and fexofenadine results in larger wheal and flare sizes in research models. This suggests that grapefruit also reduces the clinical response to fexofenadine (17603). Grapefruit juice seems to inhibit organic anion transporting polypeptide (OATP), which is a drug transporter in the gut, liver, and kidney (7046,17603,17604,22161). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

FLUVOXAMINE (Luvox) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can increase blood levels of fluvoxamine, potentially increasing the effects and adverse effects of fluvoxamine.  Details Clinical research shows that grapefruit juice inhibits metabolism and increases fluvoxamine levels and peak concentration (17675).

HALOFANTRINE Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of halofantrine, potentially increasing the effects and adverse effects of halofantrine.  Details Clinical research shows that grapefruit juice inhibits cytochrome P450 3A4 (CYP3A4) metabolism, which increases halofantrine levels and peak concentration, as well as a marker of ventricular tachyarrhythmia potential (22129).

HMG-CoA REDUCTASE INHIBITORS ("Statins") Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of statins that are metabolized by cytochrome P450 3A4 (CYP3A4), potentially increasing the effects and adverse effects of these statins. Additionally, grapefruit juice might interfere with the bioavailability of statins that are substrates of organic anion transporting polypeptides (OATP).  Details Clinical research shows that grapefruit juice inhibits metabolism and increases absorption and plasma concentrations of statins that are metabolized by CYP3A4. These include lovastatin (527,11274), simvastatin (3774,7782,22127), and atorvastatin (3227,12179,22126). Keep in mind that there is considerable variability in the effect of grapefruit juice on drug metabolism, so individual patient response is difficult to predict (7777,7781). Some statins, including pravastatin, fluvastatin, pitavastatin, and rosuvastatin, are not metabolized by CYP3A4. However, grapefruit juice might still affect the bioavailability of these statins. These statins are substrates of OATP. Grapefruit juice can inhibit OATP. Therefore, grapefruit juice may reduce the bioavailability or increase drug levels of these statins depending on the type of OATP. However, grapefruit juice affects OATP for only a short time. Therefore, separating drug administration by at least 4 hours is likely to avoid this interaction (3227,12179,17601,22126,91420).

ITRACONAZOLE (Sporanox) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can interfere with itraconazole absorption, although the clinical significance of this interaction is unclear.  Details Clinical research shows that grapefruit juice can affect itraconazole absorption and might increase or decrease itraconazole levels (310,17601,22123).

LEVOTHYROXINE (Synthroid, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can decrease blood levels of levothyroxine, potentially decreasing the effectiveness of levothyroxine.  Details Clinical research shows that grapefruit juice modestly decreases levothyroxine levels by 11% by inhibiting organic anion transporting polypeptide (OATP) (17604,22163). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

LOSARTAN (Cozaar) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of the active metabolite of losartan, potentially decreasing the clinical effects of losartan.  Details Losartan is an inactive prodrug which must be metabolized to its active form, E-3174, to be effective. In one human study, grapefruit juice reduced losartan metabolism, increased losartan AUC, and reduced the AUC of the major active losartan metabolite, E-3174 (1391).

METHADONE (Dolophine) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of methadone, potentially increasing the effects and adverse effects of methadone.  Details Clinical research shows that grapefruit juice inhibits the metabolism of methadone, increasing methadone levels and peak concentrations (17676). In one case, a 51-year-old male taking methadone 90 mg daily and no other medications was found unresponsive. The patient reported drinking grapefruit juice 500 mL daily for 3 days prior to the event. Methadone is a substrate of cytochrome P450 3A4 (CYP3A4), and grapefruit juice-induced inhibition of CYP3A4 is the likely cause of this interaction (102056).

METHYLPREDNISOLONE Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of methylprednisolone, potentially increasing the effects and adverse effects of methylprednisolone.  Details Clinical research shows that grapefruit juice can increase the plasma concentration of orally administered methylprednisolone. Grapefruit juice 200 mL three times daily given with methylprednisolone 16 mg increased methylprednisolone half-life by 35%, peak plasma concentration by 27%, and total area under the curve by 75% (3123).

NADOLOL (Corgard) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice might decrease blood levels of nadolol, potentially decreasing the clinical effects of nadolol.  Details Nadolol is a substrate of organic anion transporting polypeptide 1A2 (OATP1A2) (17603,17604,22161). Some research shows that grapefruit juice and its constituent naringin can inhibit organic anion transporting polypeptides (OATP), which can reduce the bioavailability of OATP substrates (17603,17604,22161,91427). However, preliminary clinical research shows that grapefruit juice containing a low amount of naringin does not significantly affect levels of nadolol (91422). It is not known if grapefruit juice containing higher amounts of naringin reduces the bioavailability of nadolol.

NILOTINIB (Tasigna) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of nilotinib, potentially increasing the effects and adverse effects of nilotinib.  Details Clinical research shows that grapefruit juice inhibits metabolism and increases absorption of nilotinib. Grapefruit juice increases nilotinib levels by 29% and peak concentration by 60% (17677).

ORGANIC ANION-TRANSPORTING POLYPEPTIDE SUBSTRATES (OATP) Interaction Rating = Major Do not take this combination. Severity = Moderate •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can decrease levels of drugs that are substrates of OATP.  Details In vitro and clinical research show that consuming grapefruit juice inhibits OATP, which reduces the bioavailability of oral drugs that are substrates of OATP. Various clinical studies have shown reduced absorption of OATP substrates when taken with grapefruit, including fexofenadine, acebutolol, aliskiren, celiprolol, levothyroxine, nadolol, and pitavastatin (17603,17604,18101,22126,22134,22161,22163,91420,91427,91428,112288). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction (17603,17604).

OXYCODONE (Oxycontin) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of oxycodone, potentially increasing the effects and adverse effects of oxycodone.  Details Oxycodone is metabolized by both cytochrome P450 3A4 (CYP3A4) and cytochrome P450 2D6 (CYP2D6). A small clinical study shows that grapefruit juice can increase plasma levels of oral oxycodone about 1.7-fold by inhibiting CYP3A4. While the analgesic effects of oxycodone do not seem to be affected, taking grapefruit juice along with oxycodone may theoretically increase the adverse effects of oxycodone (91423).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice does not seem to affect renal P-glycoprotein (P-gp). Theoretically, it might inhibit intestinal P-gp, but evidence is conflicting.  Details While most in vitro research shows that grapefruit products inhibit P-gp, (1390,11270,11278,11362,95976), research in humans is less clear. Two small clinical studies in healthy adults using digoxin as a probe substrate show that grapefruit juice does not inhibit P-gp in the kidneys (11277,11282). It is unclear whether this applies to intestinal P-gp, for which digoxin is not considered to be a sensitive probe (105568). Grapefruit juice has been shown to reduce levels of fexofenadine (7046,17602,112288), and increase levels of quinidine (5067,22121). However, as both of these drugs are also substrates of other enzymes and transporters, it is unclear what role, if any, intestinal P-gp has in these findings.

PITAVASTATIN (Livalo) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of pitavastatin, potentially increasing the effects and adverse effects of pitavastatin.  Details Pharmacokinetic research shows that taking grapefruit juice with pitavastatin 2-4 mg can increase blood levels of pitavastatin by 13% to 14%. Unlike simvastatin and atorvastatin, pitavastatin is not significantly metabolized by cytochrome P450 3A4 (CYP3A4) enzymes. Grapefruit juice appears to increase levels of pitavastatin by inhibiting its uptake by organic anion transporting polypeptide 1B1 (OATP1B1) into hepatocytes for metabolism and clearance from the body (22126,91420). Grapefruit juice seems to increase levels of pitavastatin to a greater degree in patients homozygous for a specific polymorphism (388A>G) in the OATP1B1 gene compared to those heterozygous for this polymorphism (91420).

PRASUGREL (Effient) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of the active metabolite of prasugrel, thereby decreasing the antiplatelet effect of prasugrel.  Details Prasugrel is a prodrug that is metabolized by cytochrome P450 3A4 (CYP3A4) into its active metabolite. A small pharmacokinetic study in healthy volunteers shows that drinking grapefruit juice 200 mL three times daily for 4 days and taking a single dose of prasugrel 10 mg with an additional 200 mL of grapefruit juice on day 3, results in a 49% lower peak plasma level and a 26% lower overall plasma exposure to the active metabolite when compared with drinking water. However, despite the reduced exposure, platelet aggregation seems to be reduced by an average of only 5% (105567). The clinical significance of this interaction is unclear.

PRAZIQUANTEL (Biltricide) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of praziquantel, potentially increasing the effects and adverse effects of praziquantel.  Details Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism of praziquantel. Plasma concentrations of praziquantel can increase by as much as 160% when administered with 250 mL of commercially available grapefruit juice (8282).

PRIMAQUINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice may increase blood levels of primaquine, potentially increasing the effects and adverse effects of primaquine.  Details Clinical research shows that grapefruit juice increases the bioavailability of primaquine by approximately 20% (22130). The clinical significance of this interaction is not clear.

QT INTERVAL-PROLONGING DRUGS Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit or grapefruit juice, especially if consumed in large amounts, can cause additive QT interval prolongation when taken with QT interval-prolonging drugs, potentially increasing the risk of ventricular arrhythmias.  Details Clinical research in healthy volunteers shows that drinking 6 liters of grapefruit juice over 6 hours prolonged the QTc by a peak amount of 14 milliseconds (ms). This prolongation was similar to the QT prolongation caused by the drug moxifloxacin. In individuals with long QT syndrome, a smaller dose of grapefruit juice, 1.5 liters, resulted in a greater peak QTc prolongation of about 30 ms (100249). The effect of smaller quantities of grapefruit juice on the QT interval is unclear.

QUETIAPINE (Seroquel) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice may increase blood levels of quetiapine, increasing the effects and adverse effects of quetiapine.  Details Quetiapine is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit can inhibit CYP3A4 (3227,3774,8283,8285,8286,22129,91427,104190). In one case report, a healthy 28-year-old female with bipolar disorder stabilized on quetiapine 800 mg daily presented with quetiapine toxicity considered to be related to consuming a gallon of grapefruit juice over the past 24 hours (108848).

QUINIDINE Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can alter blood levels of quinidine, potentially increasing or decreasing the clinical effects of quinidine.  Details Clinical research shows that grapefruit juice decreases quinidine absorption, clearance, and metabolism, and prolongs the half-life by about 20% (5067,22121).

SAQUINAVIR (Fortovase, Invirase) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of saquinavir, potentially increasing the effects and adverse effects of saquinavir.  Details Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of saquinavir (3773,22132).

SCOPOLAMINE (Transderm Scop) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of scopolamine, potentially increasing the effects and adverse effects of scopolamine.  Details Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism of scopolamine, increasing its absorption and plasma concentrations. Oral bioavailability of scopolamine can increase by 30% when administered with 150 mL of grapefruit juice (8284).

SERTRALINE (Zoloft) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice can increase blood levels of sertraline, potentially increasing the effects and adverse effects of sertraline.  Details Clinical research shows that grapefruit juice inhibits the cytochrome P450 3A4 (CYP3A4) metabolism of sertraline, increasing blood levels of sertraline (22122).

SILDENAFIL (Viagra) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of sildenafil, potentially increasing the effects and adverse effects of sildenafil.  Details Clinical research shows that grapefruit juice inhibits cytochrome P450 3A4 (CYP3A4) metabolism of sildenafil, increasing its absorption and plasma concentrations. Oral bioavailability of sildenafil can increase by 23% when administered with 500 mL of commercially available grapefruit juice (8283).

SUNITINIB (Sutent) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Unlikely •  Level of Evidence = B Grapefruit juice may slightly increase blood levels of sunitinib, potentially increasing the effects and adverse effects of sunitinib.  Details Sunitinib is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit and grapefruit juice can inhibit CYP3A4 and increase levels of some drugs metabolized by this enzyme. One small clinical study shows that drinking 200 mL of grapefruit juice three times daily can increase the bioavailability of sunitinib by 11% (91429). While this effect is unlikely to be clinically significant, patients should use caution when using grapefruit along with sunitinib. Dose adjustments may be necessary.

TACROLIMUS (Prograf) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Likely •  Level of Evidence = B Grapefruit juice can increase blood levels of tacrolimus, potentially increasing the effects and adverse effects of tacrolimus.  Details Clinical research shows that drinking grapefruit juice 200 mL daily while taking tacrolimus 3 mg daily increases the trough blood concentration of tacrolimus by approximately 3-fold in patients with connective tissue diseases (95974). A single case has also reported a 10-fold increase in tacrolimus trough levels after the ingestion of grapefruit juice over 3 days (22122). This effect is attributed to the inhibition of cytochrome P450 3A4 (CYP3A4) by grapefruit (95974).

TADALAFIL (Cialis) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, grapefruit juice might increase blood levels of tadalafil, potentially increasing the effects and adverse effects of tadalafil.  Details Animal research shows that grapefruit juice increases tadalafil serum concentrations and overall exposure, likely through inhibition of cytochrome P450 3A4 enzymes (104189).

TALINOLOL Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Grapefruit juice might decrease blood levels of talinolol, potentially decreasing the clinical effects of talinolol.  Details Clinical research suggests that grapefruit juice reduces talinolol bioavailability, likely by inhibiting intestinal uptake (22135). The clinical significance of this effect is unclear.

TERFENADINE (Seldane) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of terfenadine, potentially increasing the effects and adverse effects of terfenadine.  Details Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of terfenadine (530,22124,22125). The mechanism of action is unclear.

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can decrease blood levels of theophylline, potentially decreasing the effectiveness of theophylline.  Details Clinical research shows that grapefruit juice seems to modestly decrease theophylline levels when given concurrently with sustained-release theophylline (11013). The mechanism of this interaction is unknown.

TICAGRELOR (Brilinta) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of ticagrelor, thereby increasing the effects and adverse effects of ticagrelor.  Details Ticagrelor is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit can inhibit CYP3A4. A small clinical study shows that taking grapefruit juice with ticagrelor increases blood levels of ticagrelor more than two-fold and increases the antiplatelet activity of ticagrelor (91418).

TOLVAPTAN (Samsca) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Grapefruit juice can increase blood levels of tolvaptan, potentially increasing the effects and adverse effects of tolvaptan.  Details Tolvaptan is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit can inhibit CYP3A4. A small clinical study shows that grapefruit juice can increase the bioavailability and blood levels of tolvaptan by approximately 1.6-fold for up to 16 hours (91426).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, drinking large amounts of grapefruit juice might increase the effects and adverse effects of warfarin.  Details In one case report, a patient experienced significantly increased international normalized ratio (INR) associated with consumption of 50 ounces of grapefruit juice daily (12061). However, smaller amounts of grapefruit juice might not be a problem. In a small clinical trial, consumption of 24 ounces of grapefruit juice daily for one week had no effect on INR in males treated with warfarin (12063).

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ANTIDIABETES DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, stevia might increase the risk for hypoglycemia when combined with antidiabetes drugs.  Details Preliminary clinical research in patients with type 2 diabetes suggests that taking a single dose of stevia extract 1000 mg reduces postprandial blood glucose levels when taken with a meal (11812). However, other clinical research in patients with type 1 or type 2 diabetes suggests that taking stevioside 250 mg three times daily does not significantly affect blood glucose levels or glycated hemoglobin (HbA1C) after three months of treatment (16705).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, combining stevia or stevia constituents with antihypertensive agents might increase the risk of hypotension.  Details Stevia extract and stevioside might lower blood pressure in patients with hypertension (3745,3747,5031,11809,11810). However, other clinical research suggests that stevioside does not significantly lower blood pressure in patients with hypertension (16706).

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, stevia might decrease clearance and increase levels of lithium.  Details Animal research suggests that stevia extracts might have diuretic activity (3746,3747). Theoretically, increased reabsorption of lithium along with sodium might reduce excretion and increase levels of lithium.

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General ...Orally and topically, DHEA seems to be well tolerated when used in typical doses, short-term. However, there is some concern that long-term oral use of DHEA may be linked to a greater risk for cancer.
Most Common Adverse Effects:
Orally: Acne, headache, insomnia, mood changes, and nausea. In females, masculinization symptoms including deepening of the voice, increased size of genitals, irregular menses, oily skin, reduced breast size, and unnatural hair growth. In males, aggression, breast tenderness or enlargement (gynecomastia), urinary urgency, and testicular wasting.
Serious Adverse Effects (Rare):
Orally: Possible increased risk for cardiovascular events and various types of cancer.

Cardiovascular ...Incidences of arrhythmia (21334,47540), chest pain (21332,21333), palpitations (21332,21333,88492), hypertension, and transient ischemic attacks (21353,21354,47300) have been reported. DHEA has also been found to decrease high-density lipoprotein (HDL) levels (21344,21345,21346,21347,21348,21349) and increase triglycerides (21334).

Dermatologic ...Acne has been the most commonly reported adverse effect in human research, particularly in females (2113,2114,4242,7614,7559,12561,12574,21346,21351,21354)(21355,21356,21357,21358,21360,21361,21362,21363,21364,47300)(47355,47409,90304,103185). However, it is generally mild and may be treated by reducing the dose (7559). Incidences of contact dermatitis (47402), acneiform dermatitis (2113), greasy hair and skin (17218,21351,21355,21363,21387,21389,47355), keratosis (47402), skin rash (12574,21361,21363), erythema (21334), scalp itching (17218,21357), and skin spots (21387) have also been reported. Increased hair growth and hirsutism have been noted in several clinical trials, including the development of mild mustache in females (2114,4242,12561,12574,17218,21346,21351,21354,21355,21358) (21361,21362,21363,21370,21387,21389,21415,47300). Increased perspiration and odor have also been reported in human research (17218,21354,21356,21357).

Endocrine ...In postmenopausal patients, high doses of DHEA (1600 mg daily) induced insulin resistance, reportedly due to increased androgen levels that occurred during supplementation (21324).

Gastrointestinal ...Gastrointestinal disturbances such as nausea, diarrhea, and abdominal discomfort have been noted in human research (2111,6098,7559,12574,21348,21358,21386).

Genitourinary ...In older adults, elevated and severe urinary symptoms (as evidenced by scores of more than 20, using the American Urological Association Symptom Index for Benign Prostatic Hyperplasia [International Prostate Symptom Score]) and urinary tract infection were reported (21353). Rare incidences of abnormal menses (2114) and increased discharge (21415) have been reported. DHEA has been associated with hematuria (47300).

Hepatic ...Elevated liver enzymes have been reported following DHEA supplementation (21364,47300). However, an analysis of multiple studies in varied patient populations taking DHEA supplements found no elevations in liver enzymes (107791).

Musculoskeletal ...Incidences of asthenia, arthralgia, and myalgia, including calf cramps, have been reported (12574,21354,21358,21365,47355).

Neurologic/CNS ...In humans, dizziness, fatigue, malaise, sleep disturbances, increased dreaming, night sweats, restlessness, "painful spots," and a crawling scalp sensation have been reported (3865,21354,21363,21389). There is a case of seizure associated with DHEA use in a 30 year-old female with fragile X syndrome and no history of convulsive disorder who used DHEA to try to improve ovarian production (47344).

Ocular/Otic ...In patients with Sjögren syndrome, maculae lesions, ocular pain and dryness, and painful eye exams have been reported (21358,21363,21365).

Oncologic ...Preclinical research suggests that DHEA may increase the risk of cancer, particularly prostate, liver, breast, and pancreatic cancers (2111,10370,10401,10403,12565,21332,21333,21334,47251,47256)(47366,47388,47539). High concentrations of DHEA in postmenopausal patients have been associated with an increased risk of breast cancer (2115,6445).

Psychiatric ...DHEA-induced mania has been reported (5870,6102,7023,21383). Clinical studies have also reported anxiety, nervousness, irritability, emotional change, and depression in patients receiving DHEA (2114,21358,21360,21370).

Pulmonary/Respiratory ...Increased cough and nasal congestion have been noted in human research (3865,11334). A report of acute respiratory failure was made in clinical study evaluating the use of DHEA in patients with myotonic dystrophy (type 1) (21334).

Other ...Perceived increases in weight gain have been reported with use of DHEA (2114,21361).

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General ...Orally, grapefruit and grapefruit juice are generally well tolerated.
Serious Adverse Effects (Rare):
Orally: Allergic reactions in sensitive individuals have been reported. When large quantities are consumed, arrhythmias, mineralocorticoid excess, QT prolongation, and pseudohyperaldosteronism have been reported. There is also some concern for increased breast cancer risk with grapefruit consumption.

Cardiovascular ...Orally, consumption of pink grapefruit juice 1000 mL can cause QT prolongation and cause arrhythmias in healthy patients and worsen arrhythmias in cardiomyopathy patients (13031,91424).

Endocrine ...Orally, high doses of grapefruit juice have been observed to cause pseudohyperaldosteronism and mineralocorticoid excess (53340,53346).

Gastrointestinal ...In a case report, grapefruit juice held against the teeth resulted in enamel and tooth surface loss (53368).

Immunologic ...Orally, grapefruit can cause allergic sensitization characterized by eosinophilic gastroenteritis, urticaria, and generalized pruritus (53351,53360).

Oncologic ...Preliminary population research shows that postmenopausal adults who consume a quarter or more of a whole grapefruit daily have a 25% to 30% increased risk of developing breast cancer (14858). Grapefruit is a potent inhibitor of cytochrome P450 3A4, which metabolizes estrogen. Consuming large amounts of grapefruit might significantly increase endogenous estrogen levels and therefore increase the risk of breast cancer. More evidence is needed to validate these findings. Until more is known, advise patients to consume grapefruit in moderation.

Renal ...In population research, consumption of 240 mL/day of grapefruit juice is associated with an increased risk of kidney stones (4216,53372).

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General ...Orally, stevia and steviol glycosides appear to be well tolerated. Most minor adverse effects seem to resolve after the first week of use.
Most Common Adverse Effects:
Abdominal bloating, dizziness, headache, myalgia, nausea, and numbness.
Serious Adverse Effects (Rare):
Allergic reactions.

Gastrointestinal ...Orally, stevia and steviol glycosides such as stevioside, can cause gastrointestinal adverse effects such as abdominal fullness and nausea. However, these generally resolve after the first week of use (11809,11810).

Immunologic ...Theoretically, stevia might cause allergic reactions in individuals sensitive to plants in the Asteraceae/Compositae family (11811). Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many other herbs.

Musculoskeletal ...Orally, stevia and steviol glycosides may cause myalgia, but this generally resolves after the first week of use (11809,11810).

Neurologic/CNS ...Orally, stevia and steviol glycosides may cause headache, dizziness, and numbness (11809,11810).

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