Cranberry 500 mg with Chokeberry by herbscience

POSSIBLY INEFFECTIVE

• Cardiovascular disease (CVD). Oral chokeberry does not appear to improve body composition, cholesterol levels, blood pressure, or glycemic control in individuals with or at risk for CVD. Details: Most clinical research, including a meta-analysis of 7 clinical trials, shows that taking chokeberry does not reduce body mass index, cholesterol levels, blood pressure, or glucose levels in patients with a history of or risk factors for CVD (92374,102900,103183). The meta-analysis does, however, show that chokeberry can increase high-density lipoprotein (HDL) by around 1.5 mg/dL when compared with placebo. However, this improvement is unlikely to be clinically significant (103183).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral chokeberry is beneficial for preventing or treating age-related cognitive decline. Details: A small clinical study in healthy adults aged 40-60 years who are at risk for cognitive decline due to age and obesity shows that taking a specific chokeberry extract (Brainberry, Bioactor BV) 90 mg daily for 24 weeks improves psychomotor speed when compared with placebo. However, taking 150 mg daily has no effect. Also, neither dose improves attention, cognitive flexibility, mood, brain-derived neurotrophic factor levels, or vascular parameters such as carotid artery blood flow (105540).
• Age-related macular degeneration (AMD). Although there has been interest in using oral chokeberry for AMD, there is insufficient reliable information about the clinical effects of chokeberry for this purpose.
• Athletic performance. Limited-quality research on the use of oral chokeberry for improving athletic performance is mixed. Details: A small clinical study in semi-professional soccer players in Poland shows that taking lyophilized black chokeberry extract 6 grams daily for 90 days improves performance on a 20-meter shuttle run test when compared with placebo (111116). However, another small clinical trial in a similar study population shows that drinking chokeberry juice 200 mL daily for 7 weeks does not improve performance on the 20-meter shuttle run test when compared with placebo (111115). The disparate findings may be due to differences in the chokeberry formulations and study durations.
• Burning mouth syndrome. It is unclear if topical chokeberry is beneficial in patients with burning mouth syndrome. Details: A small clinical study in menopausal patients with burning mouth syndrome shows that rinsing with 15 mL of chokeberry juice for 5 minutes three times daily for 4 weeks reduces symptoms of burning mouth syndrome when compared to baseline (111117). The validity of these findings is limited by a lack of placebo control group.
• Cancer. Although there has been interest in using oral chokeberry for cancer, there is insufficient reliable information about the clinical effects of chokeberry for this purpose.
• Cellulite. Although there has been interest in using oral chokeberry for cellulite, there is insufficient reliable information about the clinical effects of chokeberry for this purpose.
• Diabetes. It is unclear if oral chokeberry is beneficial in patients with type 2 diabetes. Details: A small, open-label clinical study in patients with type 2 diabetes shows that drinking chokeberry juice 50 mL three times daily for 3 months does not improve fasting blood glucose, glycated hemoglobin (HbA1c), cholesterol levels, blood pressure, or measures of kidney function when compared to baseline (111118).
• Hypercholesterolemia. It is unclear if oral chokeberry is beneficial in patients with hypercholesterolemia. Details: A small clinical study in males with mild hypercholesterolemia shows that drinking chokeberry juice 250 mL daily might decrease low-density lipoprotein (LDL) cholesterol levels when compared to baseline. Chokeberry juice was consumed for 6 weeks, followed by a 6-week break, and then consumed for another 6 weeks. No reduction in LDL cholesterol levels was seen after the first 6 weeks; however, LDL cholesterol levels decreased by 17% from baseline after another 6 weeks of consumption (92369). Due to the conflicting outcomes and lack of control group, it is not clear if chokeberry lowers LDL cholesterol levels.
• Hypertension. Some limited-quality evidence suggests that oral chokeberry might lower blood pressure in patients with hypertension; however, conflicting results exist, and the available studies have all been short-term. Details: One small clinical study in patients with slightly high blood pressure or mild hypertension shows that drinking chokeberry juice 200 mL daily for 4 weeks improves systolic and diastolic blood pressure, both while awake and on average over a 24-hour period, when compared to baseline (92372). However, this study is limited by a lack of control group. Another small clinical study in patients with mild hypertension shows that drinking chokeberry juice 300 mL mixed with chokeberry powder 3 grams daily for 8 weeks reduces daytime diastolic blood pressure by 1.6 mm Hg when compared with placebo; however, this effect is modest, at best, and 24-hour ambulatory blood pressure and daytime systolic blood pressure were not improved (98086). Chokeberry juice in combination with other berries has also been evaluated for hypertension. A small clinical study in patients with mild hypertension shows that drinking a specific juice (Mana Blue or Optijuice, Tine SA), containing juice from chokeberries, grapes, cherries, and bilberries, 500 mL daily for 12 weeks modestly improves systolic blood pressure, but not diastolic blood pressure, when compared with a placebo juice (92371). It is unclear if this effect is due to chokeberry, other components of the juice, or the combination.
• Kidney failure. It is unclear if oral chokeberry is beneficial in patients with kidney failure. Details: A small clinical study in patients with chronic kidney disease and hemodialysis-induced anemia shows that taking chokeberry extract 30 mL daily for 30 days improves some measures of anemia, including levels of hemoglobin, lactate dehydrogenase, and ferritin, when compared to baseline (111120). The validity of these findings is limited by a lack of placebo control group.
• Male infertility. Although there has been interest in using oral chokeberry for male infertility, there is insufficient reliable information about the clinical effects of chokeberry for this purpose.
• Metabolic syndrome. Some limited-quality clinical research suggests that oral chokeberry might improve blood pressure and lipid levels in patients with metabolic syndrome. Details: Two small clinical studies in adults with metabolic syndrome show that taking a specific extract of chokeberry (Aronox, Naturex) 300 mg daily for 2 months reduces systolic blood pressure by 8%, diastolic blood pressure by 6%, total cholesterol levels by 6%, and low-density lipoprotein (LDL) cholesterol levels by 8% to 9%, but does not affect blood glucose levels or body composition, when compared to baseline (92363,92364). The validity of these results is limited by the lack of a control group. An open-label case series of patients with metabolic syndrome shows that taking a standardized chokeberry extract (Alixir 400 Protect, Pharmanova) 30 mL daily for 4 weeks decreases body weight when compared to baseline. It also decreases LDL cholesterol in females and total cholesterol in females with diabetes, increases high-density lipoprotein (HDL) cholesterol levels in females without diabetes, and decreases triglycerides in both males and females with diabetes, when compared to baseline (105542). The validity of these results is limited by the study design, analysis of multiple subgroups, and the lack of a control group. Another small clinical study in adults with metabolic syndrome shows that drinking a citrus juice containing chokeberry extract 5% 300 mL daily for 6 months lowers total cholesterol levels by 8% when compared to baseline and by 12% when compared with placebo (92365). However, it is unclear if these findings are due to chokeberry, other ingredients in the juice, or the combination.
• Obesity. Oral chokeberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in females with overweight or obesity and at least one risk factor for cardiovascular disease shows that drinking a combination of chokeberry, apple, blueberry, and cranberry juice 300 mL daily for 6 weeks does not reduce body weight, body mass index (BMI), or blood pressure but might improve total cholesterol and high-density lipoprotein (HDL) cholesterol when compared to baseline (111121). Additionally, a small clinical study in postmenopausal patients with abdominal obesity shows that drinking 100 mL of chokeberry juice enriched with glucomannan fiber 2 grams daily as part of a regular diet for 4 weeks reduces BMI by 3%, waist circumference by 4%, and systolic blood pressure by 8% when compared to baseline (92368). The patients in this study were sedentary and following moderately unhealthy diets. It's unclear how chokeberry juice compares to dieting or exercising to improve these outcomes. Overall, the lack of control groups limits the validity of the findings above. It is also unclear whether the findings are due to chokeberry, other ingredients, or the combination.
• Rheumatoid arthritis (RA). Although there has been interest in using oral chokeberry for RA, there is insufficient reliable information about the clinical effects of chokeberry for this purpose.
• Urinary tract infections (UTIs). It is unclear if oral chokeberry is beneficial for the prevention of UTIs. Details: A moderate-sized clinical study in elderly adults residing in nursing homes shows that drinking chokeberry juice an average of 89-156 mL daily for 3 months does not reduce UTI occurrence rate or the use of antibiotics when compared with placebo (92367). More evidence is needed to rate chokeberry for these uses.

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POSSIBLY EFFECTIVE

• Urinary tract infections (UTIs). Cranberry products may possibly reduce the risk of repeat, symptomatic UTI in females with recurrent UTI, in children, and in people susceptible to UTI following kidney transplant, urogenital surgery, or radiation therapy near the urogenital system. While some positive evidence exists, most research suggests that cranberry products do not seem to reduce the risk of UTI in older adults in institutions, pregnant patients, or adults with neuromuscular dysfunction of the bladder. Cranberry is not recommended for the treatment of UTI in any population. Details: Cranberry appears to reduce the risk of UTI in some populations but not others. In healthy females at an increased risk of UTI or history of recurrent UTI, meta-analyses of clinical trials show that cranberry products decrease the overall risk of recurrent or first-time UTI by 26% to 35% (46473,92578,96739,111407). In 2019, the American Urological Association published guidelines stating that, based on low certainty evidence, clinicians may offer cranberry tablets or juice as prophylaxis for females with recurrent UTIs. Due to a lack of compelling evidence for any specific product, the guidelines recommend choosing formulations based on availability and tolerability (100855). In 2020, the US Food and Drug Administration (FDA) approved qualified health claims stating that consuming cranberry juice in doses of at least 8 ounces daily, or cranberry supplements in doses of at least 500 mg daily, may help reduce the risk of recurrent UTI in healthy females. However, the FDA has concluded that there is limited scientific evidence to support these claims (103302). The benefits of cranberry for prevention of UTI during pregnancy are unclear. Subgroup analysis of meta-analyses suggest that cranberry supplementation does not reduce the risk of UTI in pregnant adults compared with placebo or no treatment (100855,111407). A preliminary clinical study shows that drinking cranberry juice 240 mL three times daily until delivery does not reduce the frequency of asymptomatic bacteriuria or symptomatic UTI during pregnancy, although the study was not adequately powered to detect a difference in these outcomes (16415). In contrast, one preliminary clinical trial shows that UTI frequency was reduced in 70.5% of those ingesting cranberry juice 250 mL four times daily, compared with only 32% of those taking placebo (93670). In children, a meta-analysis shows that taking cranberry products probably reduces the risk of subsequent symptomatic UTIs by up to 54% compared with placebo or no treatment, but does not specify a particular formulation (111407). Clinical trials show that daily consumption of cranberry syrup (Pharmatoka), cranberry juice (Cranberry UR-50, Kikkoman Company) 100 mL, cranberry-lingonberry juice 50 mL, and cranberry extract (Anthocran) 120 mg reduce the risk of UTI recurrence in children (46452,96733,96737,108055). In contrast, another clinical trial shows that drinking cranberry juice (Ocean Spray Cranberries, Inc) 5 mL/kg daily for 6 months does not reduce the incidence of recurrent UTI when compared with placebo, although it does decrease the total number of UTI episodes and length of antimicrobial therapy per child (46470). In older, institutionalized adults, a meta-analysis of 5 studies evaluating the effectiveness of cranberry products shows little or no benefit in preventing symptomatic, culture-verified UTIs (111407). A clinical study in females residing in long-term care (LTC) facilities shows that taking a specific cranberry supplement (Ellura, Pharmatoka) once daily for 1 year does not reduce the incidence of UTI or asymptomatic bacteriuria (92517). However, clinical trials of cranberry products in elderly patients in LTC facilities suggest that cranberry may be more effective in patients at a higher risk for UTIs, such as those with diabetes, long-term catheterization, or recurrent UTIs (90041,108055), and in patients with E. coli-related UTIs (46389,46472). In one small study, providing all patients living in a LTC facility with 4 ounces of cranberry juice or six tablets of a specific concentrated cranberry product (Azo-Cranberry, i-Health, Inc.) daily for 13 months decreased the facility's overall monthly UTI rate from 27.7 to 20.7 (46492). In another clinical trial, taking cranberry juice cocktail (Ocean Spray Cranberries, Inc) 300 mL daily for 6 months decreased the rate of asymptomatic bacteriuria plus pyuria by 13% in older females living in institutional settings (7008). In another clinical trial, taking a cranberry capsule 500 mg, standardized to 1.8% PACs, twice daily for 12 months decreased the risk of UTI by around 26% in patients at high-risk for UTI, including those with catheters, diabetes, or at least one UTI in the previous 12 months (90041). Meta-analyses and clinical research show that cranberry products do not reduce the risk of UTI associated with neurogenic bladder, neuromuscular dysfunction, or insufficient bladder emptying in adults or children (2811,6759,11980,46379,46425,46473,90044,92578,96737,108055,111407). However, one study found benefit in patients with neurogenic bladder due to spinal cord injury taking cranberry capsules (Cran-Max, Proprietary Nutritionals, Inc.) 500 mg daily (46443). Cranberry products have also been evaluated in a variety of other high-risk populations, with mixed results. A meta-analysis of 7 studies shows that cranberry products reduce the risk of UTIs in people with increased susceptibility to UTI due to an intervention (e.g., kidney transplant, radiotherapy to urogenital system, or urogenital surgery) when compared with placebo (111407). Cranberry extracts do not seem to reduce the risk of UTIs in individuals undergoing hysterectomy and/or anterior vaginal repair (46465), pelvic floor surgery (104245), or in patients with multiple sclerosis (46496,111407). Taking cranberry powder capsules (NurtiCran90, Petefa AB) 550 mg three times daily for 5 days does not reduce the UTI rate at days 5 or 14 when compared with placebo in postoperative females with hip fracture receiving a urinary catheter; however, the study was not adequately powered to detect a difference in this outcome (96734). Other preliminary clinical research in elderly males with benign prostatic hyperplasia and a recent UTI shows that taking a standardized cranberry extract (Anthocran) 120 mg daily for 60 days reduces the UTI recurrence rate by about 62% when compared with placebo (96735). Cranberry supplements have been studied in a variety of formulations, but it is unclear whether certain cranberry formulations are better than others (111407). Most positive studies utilized oral cranberry EXTRACTS in tablet, powder, or capsule form (6760,17210,46366,46432,93669,111407). Some products (Cranberry Supreme, GNC; Cranpac, IPCA Laboratories), taken as 200 mg twice daily, were standardized to provide 100-120 mg of proanthocyanidins (PACs) daily (46432). Some of these studies used capsules containing 400 mg cranberry solids twice daily (6760) or Natural Cranberry Extract (Solgar Vitamin and Herb Co.) 800 mg twice daily (17210). However, a clinical study in healthy females with a history of UTIs shows that taking a specific cranberry extract product (Urophenol; Diana Food) does not reduce the risk of symptomatic UTI when taken at a dose of 120 mg twice daily, standardized to 15% PACs, or at a dose of 1 mg twice daily, standardized to 1% PACs. A subgroup analysis suggests that the high dose may have modest benefit in those with less than 5 UTIs a year (108054). Cranberry JUICE or syrup has yielded mixed results for the prevention of UTI in patients with a history of recurrent UTIs, with some showing significant benefit (8253,46366,96736,111407). These studies used cranberry juice 240-250 mL 1-3 times daily (46366,96736), cranberry syrup, or a combination beverage containing cranberry juice plus lingonberry juice (Maija) 50 mL daily (8253). However, other studies found no significant improvement when compared with placebo (17524,46471,90047), although some of these studies may have been inadequately powered to detect a difference (17524,46471). Cranberry products have also been compared with other treatments including antibiotics and probiotics for preventing recurrent UTI, but the results are unclear. A meta-analysis suggests that cranberry products reduce the risk of symptomatic UTIs compared to probiotics. The analysis also showed no difference in the risk of UTI between cranberry products and antibiotics, but the precision of included studies was poor (111407). In one study, taking cranberry extract capsules (Cran-Max; Proprietary Nutritionals, Inc) 500 mg daily for 6 months was as effective as trimethoprim 100 mg daily in elderly females with recurrent UTI (16720). However, taking this same cranberry product twice daily for 12 months was less effective than trimethoprim-sulfamethoxazole 480 mg once daily in younger premenopausal individuals (17176). Additional research in children with vesicoureteral reflux (VUR) shows that daily consumption of cranberry products results in UTI recurrence rates equivalent to those obtained with prophylactic antibiotics. Cranberry juice (Cranberry UR-50, Kikkoman Company) 100 mL daily was equally effective to cefaclor 5-10 mg/kg daily; cranberry syrup (Pharmatoka) 0.2 mL/kg daily was equally effective to trimethoprim 0.2 mL/kg daily (96737).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related cognitive decline. It is unclear if oral cranberry is beneficial for age-related cognitive decline. Oral cranberry may be beneficial for improving visual episodic memory in healthy, elderly adults, but its effects on other aspects of cognition are unclear. Details: A clinical study in healthy adults aged 50-80 years shows that taking a freeze-dried cranberry powder 4.5 grams twice daily (standardized to provide 281 mg proanthocyanidins daily), provided as a sachet and added to food or beverage for 12 weeks, improves visual episodic memory performance during a memory and recall test (Rey Complex Figure Test), but does not appear to affect other measures such as attention, orientation, fluency, language, processing speed, or short-term memory, when compared with placebo (108564). Cranberry supplementation also does not appear to affect grey matter structure; however, due to the low number of patients who completed a baseline and follow-up MRI, this study may not have been adequately powered to detect a difference between groups.
• Benign prostatic hyperplasia (BPH). Preliminary clinical research suggests that oral cranberry is beneficial for reducing BPH symptoms. Details: Preliminary clinical research shows that taking powdered dried cranberry fruit 500 mg three times daily for 6 months improves lower urinary symptoms and reduces prostate specific antigen (PSA) levels when compared with no treatment in patients 45 years of age or older with elevated PSA levels, a negative prostate biopsy, and clinically confirmed non-bacterial prostatitis (17126). Another small study in those 45 years of age and older without elevated PSA levels shows that taking a specific dried cranberry powder (Flowens, Naturex-DBS, LLC) 250-500 mg daily for 6 months reduces lower urinary tract symptoms and improves voiding and storage symptoms when compared with placebo (96738).
• Cancer. Although there has been interest in using oral cranberry for cancer, there is insufficient reliable information about the clinical effects of cranberry for this condition.
• Cardiovascular disease (CVD). Although some research suggests that oral cranberry may modestly improve some CVD risk factors, it is unclear if it is beneficial for CVD prevention. Details: A meta-analysis of 10 clinical studies shows that cranberry juice or cranberry extract seems to reduce systolic blood pressure by 3.6 mmHg and body mass index by 0.3 kg/m2 when compared with placebo. However, these improvements are unlikely to be clinically significant, and cranberry does not appear to improve diastolic blood pressure, lipid levels, glycemic control, or waist circumference (102849). The generalizability of these results is limited, as the study populations ranged from healthy adults to those with type 2 diabetes, metabolic syndrome, or coronary heart disease. A clinical crossover study in patients who are overweight or obese and have elevated blood pressure shows that drinking cranberry juice 250 mL twice daily for 8 weeks reduces ambulatory diastolic blood pressure by 2 mmHg during daytime hours, but does not improve systolic blood pressure, glycemic control, or lipid levels, when compared with placebo (108059). The validity of these findings is limited due to short duration of treatment and broad heterogeneity of patient baseline characteristics.
• Catheter-related infections. Although there has been interest in using oral cranberry for catheter-related infections, there is insufficient reliable information about the clinical effects of cranberry for this condition.
• Chronic fatigue syndrome (CFS). Although there has been interest in using oral cranberry for CFS, there is insufficient reliable information about the clinical effects of cranberry for this condition.
• Diabetes. It is unclear if oral cranberry is beneficial for diabetes. Details: A small clinical trial shows that taking cranberry supplements orally does not improve fasting serum glucose, glycated hemoglobin (HbA1C), fructosamine, triglycerides, high-density lipoprotein (HDL) cholesterol, or low-density lipoprotein (LDL) cholesterol levels in patients with type 2 diabetes (11328).
• Helicobacter pylori. There is conflicting evidence regarding the use of oral cranberry for Helicobacter pylori eradication, either as a standalone treatment or in combination with standard triple therapy. Details: Two small clinical studies show that taking cranberry juice 480-500 mL, containing 88 mg proanthocyanidins (PACs), daily in two divided doses for 2-3 months can modestly increase the H. pylori eradication rate at 8 weeks, but not at 2 weeks, when compared with placebo. However, the eradication rate was only 20% or less, which is much lower than that obtained with conventional triple therapy (46388,104248). Lower doses, as either cranberry juice or cranberry powder, do not seem to improve H. pylori eradication rates. Cranberry juice containing only 23 mg or 44 mg PACs or cranberry powder containing 36 mg or 72 mg PACs did not demonstrate benefit when compared with placebo (104248). Cranberry juice has also been studied in combination with standard triple therapy. Preliminary clinical research shows that taking cranberry juice 250 mL daily for 3 weeks along with omeprazole, amoxicillin, and clarithromycin for one week does not increase the eradication rate when compared with triple therapy plus placebo. However, the combination treatment increased the rate of H. pylori eradication when only females were considered (46439). A meta-analysis of 4 small clinical studies, including three studies already discussed, shows that taking cranberry, either as a juice or a dried powder, does not improve H. pylori eradication rate when compared with placebo, regardless of treatment duration (108060). The validity of these findings is limited by the high heterogeneity of the included studies and incomplete reporting. In asymptomatic children aged 6-16 years old with H. pylori, one clinical study shows that drinking cranberry juice 200 mL, with live or heat-killed Lactobacillus johnsonii 80 mL, daily for 3 weeks eradicates H. pylori in 15% to 22% of patients, compared with 1.5% of those receiving placebo. However, these rates are lower than those typically obtained with conventional triple therapy (46441).
• Hyperlipidemia. Oral cranberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Drinking a combination of cranberry, blueberry, apple, and chokeberry juice 300 mL daily for 6 weeks appears to decrease total cholesterol and increase high-density lipoprotein (HDL) cholesterol when compared to baseline in females with overweight or obesity and at least one risk factor for cardiovascular disease (111233). However, the validity of the study is limited by its small size, short duration, and lack of a comparator group. It is unclear if these effects are due to cranberry, other ingredients, or the combination.
• Kidney stones (nephrolithiasis). It is unclear if oral cranberry is beneficial for reducing the risk of kidney stones. Details: Although some preliminary clinical research shows that drinking cranberry juice 500 mL diluted in 1500 mL water daily for 2 weeks can decrease urinary excretion of oxalate in healthy males, which suggests a decreased risk of kidney stone formation (46371), other preliminary clinical research shows that both cranberry juice and concentrated cranberry extracts can increase urinary oxalate levels, suggesting an increased risk of stone formation (7074,46393).
• Memory. It is unclear if oral cranberry is beneficial for memory. Details: Preliminary clinical research in cognitively intact older adults shows that taking cranberry juice 16 ounces twice daily for 6 weeks does not improve memory when compared with placebo (46390).
• Metabolic syndrome. It is unclear if oral cranberry is beneficial for metabolic syndrome. Details: Preliminary clinical research shows that drinking cranberry juice 240 mL twice daily for 8 weeks can increase plasma antioxidant capacity when compared with placebo in adults with metabolic syndrome. However, cranberry juice does not appear to affect blood pressure, blood glucose, serum lipids, or markers of inflammation when compared with placebo in these patients (46467).
• Nonalcoholic fatty liver disease (NAFLD). It is unclear if oral cranberry is beneficial for NAFLD. Details: Preliminary clinical research in adults with NAFLD shows that adding cranberry extract 288 mg daily to a weight loss diet for 12 weeks does not appear to affect body weight, liver enzymes, lipid levels, or steatosis grade when compared with placebo. Cranberry extract may moderately reduce insulin levels and insulin resistance (104249). However, the clinical impact of these reductions is unclear. Another clinical trial in adults with NAFLD shows that taking dried cranberry powder 144 mg daily after lunch for 6 months improves steatosis grade as measured by ultrasound, insulin sensitivity, and levels of total cholesterol and triglycerides, but does not affect liver enzyme levels, when compared with placebo. All patients also consumed a reduced-calorie diet and an undefined dose of supplemental vitamin E (108058).
• Obesity. Oral cranberry has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in females with overweight or obesity and at least one risk factor for cardiovascular disease shows that drinking a combination of cranberry, blueberry, apple, and chokeberry juice 300 mL daily for 6 weeks does not reduce body weight, body mass index (BMI), or blood pressure but might improve total cholesterol and high-density lipoprotein (HDL) cholesterol when compared to baseline (111233). However, the validity of these findings is limited by the small study size, short duration, and lack of a comparator group. It is unclear if these effects are due to cranberry, other ingredients, or the combination.
• Overactive bladder. It is unclear if oral cranberry is beneficial for overactive bladder. Details: Preliminary clinical research in otherwise healthy females shows that taking dried cranberry powder 500 mg daily for 24 weeks can reduce daily micturition by 16% and urgency episodes by 57% when compared with placebo. Patients taking cranberry powder also reported an improvement in their own perception of their bladder condition when compared with placebo (104246). Limitations of this study include a short duration, lack of a run-in period, and high drop-out rate, which interfered with the ability to meet power.
• Peristomal lesions. Although there has been interest in using oral cranberry for peristomal lesions, there is insufficient reliable information about the clinical effects of cranberry for this condition.
• Prostate cancer. It is unclear if cranberry is beneficial for preventing prostate cancer recurrence. Details: Clinical research shows that taking cranberry powder (Pacran, Naturex) 1500 mg for a mean of 30 days prior to radical prostatectomy for prostate cancer does not improve prostate tissue markers when compared with taking placebo. However, levels of prostate tissue antigen decreased by approximately 22% when compared with baseline (105127).
• Radiation-induced cystitis. Evidence for the use of cranberry juice in the prevention of radiation-induced cystitis is conflicting. Details:One small clinical study in individuals with prostate cancer shows that taking 200 mg of a cranberry extract standardized to 30% proanthocyanidins (Monoselect Macrocarpon; PharmExtracta) once daily during external beam radiotherapy for 6-7 weeks reduces the risk of lower UTI by 64% when compared with placebo (92579). However, other preliminary clinical research shows that taking cranberry capsules, standardized to contain a total of 72 mg proanthocyanidins, daily during radiation treatment for prostate cancer and for two weeks post-treatment, does not improve pain, burning, nocturia, or urinary flow symptoms from radiation-induced cystitis when compared with a beetroot placebo (104247). Additionally, preliminary clinical research in patients receiving radiotherapy for bladder or cervical cancer shows that consuming cranberry juice 250 mL daily for 2 weeks does not seem to reduce the incidence of UTIs (46469).
• Rheumatoid arthritis (RA). It is unclear if cranberry juice is beneficial in RA. Details: A clinical study in adults with RA shows that drinking reduced-calorie cranberry juice 250 mL twice daily in addition to taking fish oil 1 gram three times daily for 90 days improves disease activity score (DAS28-CRP) when compared with no supplementation. However, this combination was similarly effective to patients taking fish oil alone, suggesting that any benefits may be due to fish oil, as opposed to cranberry juice (108057).
• Upper respiratory tract infection (URTI). It is unclear if oral cranberry is beneficial for the prevention or treatment of URTIs. Details: Clinical research shows that drinking a cranberry juice beverage 450 mL daily for 70 days does not decrease the incidence of cold or flu, but may reduce cold and flu symptoms, when compared with placebo in healthy adults (90046).
• Urinary odor. It is unclear if oral cranberry is beneficial for urinary odor. Details: Preliminary clinical research shows that cranberry juice cocktail might reduce urinary odors when given orally on a regular basis to patients with urinary incontinence (3333,3334,8254). Cranberry juice cocktail up to 237 mL three times daily for up to 4 weeks has been used (3334). More evidence is needed to rate cranberry 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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POSSIBLY EFFECTIVE

• Benign prostatic hyperplasia (BPH). Taking oral pumpkin seed or pumpkin seed oil may improve symptoms of BPH. Details: One study in patients with BPH shows that taking pumpkin seed 5 grams twice daily for 12 months may be more effective for controlling symptoms than pumpkin seed extract 1000 mg twice daily (92383). A specific pumpkin seed extract (Prosta Pink Forte) 1-2 capsules daily for 12 weeks has also been used (11231). Some preliminary clinical research also suggests that taking pumpkin seed oil (Prostafit, EuRho Vital) two tablets daily for 6 months may be as effective as the medication prazosin (92382). Pumpkin seed oil has also been compared with tamsulosin. A clinical study comparing pumpkin seed oil 360 mg twice daily to tamsulosin 0.4 mg once nightly for 3 months shows that both treatment groups report improvements in BPH symptoms and quality of life when compared with baseline, although improvement appears greater in the tamsulosin group, specifically when measured at 1 month and 3 months. In the pumpkin seed oil group, adverse effects were reported in 0% of patients, compared with 15% of patients taking tamsulosin (107842). The validity of this study is limited due to the short duration of treatment. Pumpkin seed oil or extracts have also been studied in combination with saw palmetto (6777), with saw palmetto, nettle root, and lemon extracts plus beta carotene (5093), and with saw palmetto, small flowered willow herb, lycopene, and pygeum (92379).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Androgenic alopecia. Oral pumpkin seed oil might improve hair regrowth in males with mild to moderate hair loss. Details: Clinical research in males with mild to moderate hair loss shows that taking pumpkin seed oil (Octa Sabal Plus, Dreamplus Co. Ltd.) 400 mg daily in divided doses for 24 weeks increases hair count by 30% when compared with placebo. Self-rated improvement and satisfaction scores were 62% and 52% with pumpkin seed oil and placebo, respectively (92378). Clinical research in patients with female pattern hair loss shows that applying 1 mL of pumpkin seed oil to the scalp daily for 30 days improves hair regrowth similarly to minoxidil 5% foam, 1 mL daily (104974).
• Interstitial cystitis. Although there is interest in using oral pumpkin for interstitial cystitis, there is insufficient reliable information about the clinical effects of pumpkin for this condition.
• Intestinal parasite infection. Although there is interest in using oral pumpkin for intestinal parasite infection, there is insufficient reliable information about the clinical effects of pumpkin for this condition.
• Overactive bladder. Oral pumpkin seed oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in females with overactive bladder shows that taking a specific combination product (Granu Fink femina, Omega Pharma) containing pumpkin seed oil 227 mg, sweet sumac bark extract 56 mg, and hops cone extract 18 mg three times daily for 12 weeks decreases the frequency of urination and leakage and improves quality of life when compared to baseline (103253). The validity of these findings is limited by the lack of a control group. Additionally, it is unclear if these findings are due to pumpkin seed oil, other ingredients, or the combination.
• Urinary tract infections (UTIs). Although there is interest in using oral pumpkin for UTIs, there is insufficient reliable information about the clinical effects of pumpkin for this condition. More evidence is needed to rate pumpkin for these uses.

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POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts, short term. Capsules and juices containing chokeberry have been used with apparent safety in clinical studies lasting up to 90 days (92363,92364,92366,92368,92369,92371,92372,92374,92375,98086)(111115,111116).

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

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LIKELY SAFE . .when used orally and appropriately. Cranberry juice up to 300 mL daily and cranberry extracts in doses up to 800 mg twice daily have been safely used in clinical trials (3333,3334,6758,6760,7008,8252,8253,8254,8995,11328) (16415,16720,17100,17126,17176,17210,17524,46379,46388,46389)(46390,46425,46439,46443,46465,46456,46466,46467,46469,46471)(46496,46499,90044,102847,111407).

CHILDREN: LIKELY SAFE
when cranberry juice is consumed in amounts commonly found in the diet (2811,6759,46441,46452,46470,111407). There is insufficient reliable information available about the safety of cranberry when used in medicinal amounts in children.

PREGNANCY AND LACTATION: LIKELY SAFE
when consumed in amounts commonly found in the diet. There is insufficient reliable information available about the safety of cranberry when used therapeutically during pregnancy or lactation; avoid using.

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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 used orally and appropriately in amounts commonly found in foods.

POSSIBLY SAFE ...when the seed or seed oil is used orally and appropriately in medicinal amounts, short-term. Pumpkin seed has been used with apparent safety in a dose of up to 10 grams daily for up to 12 months (92383). Pumpkin seed oil has been used with apparent safety in a dose of up to 400 mg daily for up to 6 months (92378). There is insufficient reliable information available about the safety of pumpkin seed oil when used topically.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using amounts greater than those found in food.

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, chokeberry might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.  Details Clinical and in vitro research suggests that chokeberry extract can temporarily inhibit platelet aggregation and decrease clot formation (92364,92427).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, chokeberry might increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Some clinical research shows that chokeberry decreases levels of blood glucose in some patients with diabetes (92373). However, other clinical research suggests that chokeberry has no significant effect on blood glucose levels (111118).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, chokeberry might increase levels of drugs metabolized by CYP3A4.  Details In vitro research shows that chokeberry inhibits CYP3A4 (92425). In humans, there is one case report of a drug interaction with trabectedin, a CYP3A4 substrate, which is hypothesized to have been caused by chokeberry inhibition of CYP3A4 (92426).

TRABECTEDIN (Yondelis) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, chokeberry might increase the effects and adverse effects of trabectedin.  Details In one case report, a patient drinking chokeberry juice developed rhabdomyolysis induced by trabectedin, a cytochrome P450 3A4 (CYP3A4) substrate. It is possible that inhibition of CYP3A4 by chokeberry juice might have inhibited the metabolism of trabectedin and increased trabectedin levels in this patient (92426).

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ATORVASTATIN (Lipitor) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cranberry might increase levels and adverse effects of atorvastatin.  Details In one case report, a patient taking atorvastatin experienced upper back pain, rhabdomyolysis, and abnormal liver function after drinking cranberry juice 16 ounces daily for 2 weeks. Theoretically, this may have been caused by inhibition of cytochrome P450 3A4 (CYP3A4) enzymes by cranberry juice, as atorvastatin is a CYP3A4 substrate. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice (90042). Patients taking atorvastatin should avoid large quantities of cranberry juice.

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, cranberry might increase the levels and adverse effects of CYP2C9 substrates. However, research is conflicting.  Details There is contradictory evidence about the effect of cranberry on CYP2C9 enzymes. In vitro evidence suggests that flavonoids in cranberry inhibit CYP2C9 enzymes (10452,11115,90048). However, clinical research shows that cranberry juice does not significantly affect the levels, metabolism, or elimination of the CYP2C9 substrates flurbiprofen or diclofenac (11094,90048). Also, in patients stabilized on warfarin, drinking cranberry juice 250 mL daily for 7 days does not significantly increase the anticoagulant activity of warfarin, a CYP2C9 substrate (15374). Additional pharmacokinetic research shows that cranberry juice does not increase peak plasma concentrations or area under the concentration-time curve of warfarin (15393).

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cranberry might increase the levels and adverse effects of CYP3A4 substrates.  Details A case of upper back pain, rhabdomyolysis, and abnormal liver function has been reported for a patient taking atorvastatin, a CYP3A4 substrate, in combination with cranberry juice 16 ounces daily for 2 weeks. Creatinine kinase and liver enzymes normalized within 2 weeks of stopping cranberry juice (90042). Also, animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine, a CYP3A4 substrate, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control (46420).

DICLOFENAC (Voltaren, others) Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, cranberry might modestly increase the levels and adverse effects of diclofenac.  Details In vitro evidence suggests that cranberry juice inhibits diclofenac metabolism by human liver microsomes (90048). However, drinking cranberry juice does not seem to affect diclofenac metabolism in humans (90048).

NIFEDIPINE (Procardia) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, cranberry might increase the levels and adverse effects of nifedipine.  Details Animal research suggests that cranberry juice, administered intraduodenally 30 minutes prior to nifedipine treatment, inhibits nifedipine metabolism and increases the area under the concentration-time curve by 1.6-fold compared to control (46420). This interaction has not been reported in humans.

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, cranberry might increase the levels and adverse effects of warfarin. However, research is conflicting.  Details There is contradictory evidence about the effect of cranberry juice on warfarin. Case reports have linked cranberry juice consumption to increases in the international normalized ratio (INR) in patients taking warfarin, resulting in severe spontaneous bleeding and excessive postoperative bleeding (10452,12189,12668,21187,21188,21189,46378,46396,46411)(46415,90043). Daily consumption of cranberry sauce for one week has also been linked to an increase in INR in one case report (16816). In a small study in healthy young males, taking a high dose of 3 grams of cranberry juice concentrate capsules, equivalent to 57 grams of fruit daily, for 2 weeks produced a 30% increase in the area under the INR-time curve after a single 25-mg dose of warfarin (16416). However, 3 very small clinical studies in patients stabilized on warfarin reported that cranberry juice 250 mL once or twice daily for 7 days (27% cranberry juice or pure cranberry juice) or 240 mL once daily for 14 days does not significantly increase INR or affect plasma warfarin levels (15374,17124,90045). The reasons for these discrepant findings are unclear. It is possible that the form and dose of cranberry may play a role, as cranberry extracts and juices contain different constituents. Additionally, an in vitro study evaluating 5 different cranberry juices found varying effects, with only a cranberry concentrate, and not diluted cranberry juices, inhibiting CYP2C9. However, this concentrate did not inhibit CYP2C9 activity in humans (108062).

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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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LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Pumpkin might reduce excretion and increase levels of lithium.  Details Pumpkin is thought to have diuretic properties (92383). Theoretically, this might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

(Read more about PUMPKIN)

General ...Orally, chokeberry seems to be well tolerated.
Most Common Adverse Effects:
Orally: Constipation, diarrhea, nausea, stomach cramps, vomiting.

Gastrointestinal ...Orally, chokeberry juice may cause adverse gastrointestinal effects. In one small clinical study, around 14% of patients reported constipation, diarrhea, or gastrointestinal motility issues while drinking 100 mL of chokeberry juice daily for 90 days (92375). In another small clinical study, around 53% of patients reported diarrhea, loss of appetite, nausea, stomachache, stomach cramps, or vomiting while drinking 100 mL of chokeberry juice twice daily for 6 weeks (111119).

(Read more about CHOKEBERRY)

General ...Orally, cranberry seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea and gastrointestinal discomfort.

Dermatologic ...Orally, skin redness and itching has been reported in one patient (46389).

Gastrointestinal ...In very large doses, for example 3-4 L per day of juice, cranberry can cause gastrointestinal upset and diarrhea, particularly in young children (46364). There are reports of abdominal and gastrointestinal discomfort after taking cranberry tablets, extracts, and juice in clinical trials (16720,46379,111407). Nausea, vomiting, and diarrhea have also been reported with consumption of lower doses of cranberry juice cocktail, 16 ounces per day, equivalent to about 4 ounces cranberry juice, for several weeks (16415).

Genitourinary ...Vulvovaginal candidiasis has been associated with ingestion of cranberry juice (46374). Clinical research suggests that ingestion of cranberry juice may be associated with vaginal itching and vaginal dryness (46471). One patient in clinical research stopped taking dried cranberry juice due to excessive urination (46437), and an isolated case of nocturia following ingestion of cranberry tablets has been reported (16720).

Hematologic ...Thrombocytopenia has been reported as an adverse event to cranberry juice (46459).

Other ...An isolated case of sensitive swollen nipples after taking cranberry tablets has been reported (16720).

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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, pumpkin products are generally well tolerated.
Most Common Adverse Effects:
Orally: Abdominal discomfort, diarrhea, nausea, and vomiting.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis.

Dermatologic ...There are two case reports of adult females developing substantial transient hair loss 1-3 weeks after consumption of a meal containing either bitter-tasting pumpkin or undefined squash. This adverse effect was attributed to a high concentration of cucurbitacin, which is commonly found in wild pumpkins (104535).

Gastrointestinal ...Orally, pumpkin seed oil has been reported to cause mild abdominal discomfort in clinical trials (5093,92378). There are also two case reports of adults developing severe nausea, vomiting, and diarrhea following consumption of a meal containing either bitter-tasting pumpkin or undefined squash. These adverse effects were attributed to a high concentration of cucurbitacin, which is commonly found in wild pumpkins (104535).

Immunologic ...Orally, pumpkin seed oil and pumpkin pulp have been reported to cause anaphylactic reactions in children and adults. A case review highlights 4 cases of anaphylaxis in children (3 from pumpkin pulp, 1 from pumpkin seeds), and 7 cases in adults (1 from pumpkin flesh, 6 from pumpkin seeds). Symptoms of anaphylaxis include urticaria, angioedema of the lips or face, dyspnea, dysphagia, and oropharyngeal itching and swelling. A case report describes a 2-year-old male presenting with urticaria, swollen lips, and increased dyspnea 10 minutes after ingesting pumpkin seeds. The patient was found to have elevated allergen-specific immunoglobulin E (IgE) and a positive skin-prick test for pumpkin seeds. Symptoms resolved after treatment with epinephrine, systemic glucocorticoids, salbuterol, and antihistamines (107843).
There may also be concern for allergic reaction due to inhalation or topical exposure. One case report describes an 8-year-old child developing anaphylaxis while carving a pumpkin; another highlights that inhalation of pumpkin seed flour may have potentiated anaphylaxis in 3 individuals following the ingestion of pumpkin seeds (107843). Further research is necessary to assess the relationship between anaphylaxis and route of administration.

(Read more about PUMPKIN)