El Dorado by D'Adamo Personalized Nutrition

POSSIBLY EFFECTIVE

• Canker sores. Some evidence shows that berberine gel applied to canker sores may reduce pain and the size of the sores, but it has not been compared to conventional treatments. Details: Some clinical research shows that applying a gel containing berberine 5 mg/gram four times daily for 5 days can reduce pain by 26% and ulcer size by 30% when compared with placebo in patients with minor recurrent canker sores. Erythema and exudation also appear to be improved (91955).
• Diabetes. Berberine seems to moderately reduce blood glucose in people with type 2 diabetes; it may provide additional benefit when given with conventional medications. Details: Some clinical research shows that taking berberine 500 mg 2-3 times daily for 2-4 months can reduce glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and postprandial glucose (PPG) in subjects with type 2 diabetes when compared with placebo, and may be similarly effective to metformin 500 mg 2-3 times daily or rosiglitazone 4 mg daily (20579,34247,34265,110099). Large meta-analyses show that taking berberine, 0.9-3 grams in 2-3 divided doses daily for 1-11 months, in combination with lifestyle interventions, can reduce FPG by 10-16 mg/dL, PPG by 27-34 mg/dL, and HbA1c by 0.4% to 0.7% when compared with lifestyle interventions alone. Also, taking berberine in combination with oral hypoglycemic drugs appears to lower FPG by 12-19 mg/dL, PPG by 18-24 mg/dL, and HbA1c by 0.6% to 0.9% when compared with hypoglycemic drugs alone (91956,110097). Berberine has also been evaluated in combination with other ingredients. A small clinical study in patients with type 2 diabetes shows that taking berberine 500 mg with Bifidobacterium adolescentis 100 million colony-forming units (CFU) twice daily for 16 weeks reduces FPG by 10 mg/dL, PPG by 28 mg/dL, and HbA1c by 0.22% when compared with placebo (110099). Another clinical study in patients with type 2 diabetes shows that taking berberine 600 mg twice daily with a multi-strain probiotic supplement, containing more than 50 billion CFU, once daily for 12 weeks reduces postprandial cholesterol by 15 mg/dL and postprandial low-density lipoprotein (LDL) cholesterol by 9 mg/dL when compared with placebo. Postprandial triglyceride levels were also improved, while postprandial levels of high-density lipoprotein (HDL) cholesterol were not affected (110100).
• Helicobacter pylori. Oral berberine, when taken with amoxicillin and a proton pump inhibitor (PPI) with or without clarithromycin, might be as effective as bismuth-containing quadruple therapy (BQT), vonoprazan quadruple therapy, and PPI-based triple therapy for eradication of Helicobacter pylori. Details: Most studies evaluate berberine in combination with an antibiotic and acid blocker for the treatment of H. pylori infection. Open-label clinical studies in patients with treatment-naïve H. pylori infection shows that taking berberine 300-500 mg with amoxicillin 1 gram and an acid reducer such as esomeprazole 20 mg, rabeprazole 10 mg, or vonoprazan 20 mg, with or without clarithromycin 500 mg, 2-3 times daily for 14 days is non-inferior to BQT, vonoprazan quadruple therapy (vonoprazan, amoxicillin, clarithromycin, bismuth), and rabeprazole quadruple therapy (rabeprazole, amoxicillin, clarithromycin, bismuth) for H. pylori eradication and clinical symptom improvement. Eradication rates were around 70% to 91% and 69% to 90% in the berberine- and bismuth-containing groups, respectively. BQT is a guideline-recommended treatment regimen for H. pylori eradication (97234,111697). Also, berberine triple therapy appears to be better tolerated when compared with BQT. Quadruple therapy consisted of amoxicillin, rabeprazole, clarithromycin, and bismuth tartrate (110107). A smaller clinical study in patients with H. pylori-associated duodenal ulcers shows that taking berberine 300 mg three times daily for 6 weeks is more effective for eradicating H. pylori than taking ranitidine 150 mg twice daily, but is less effective for promoting ulcer healing (34319).
• Hyperlipidemia. Clinical research shows that taking berberine orally, alone or in combination with other ingredients, reduces total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides in people with hyperlipidemia. Details: Meta-analyses of clinical research in people with hyperlipidemia or nonalcoholic fatty liver disease (NAFLD) show that berberine reduces total cholesterol by 13-32 mg/dL, triglycerides by up to 34 mg/dL, LDL cholesterol by 10-26 mg/dL, and apolipoprotein B by 0.25 g/L when compared with control or lifestyle interventions. However, the meta-analyses conflict on the effect of berberine on HDL cholesterol, with the studies in patients with hyperlipidemia showing that it reduces HDL cholesterol by 2-3 mg/dL while the analysis in patients with NAFLD shows that berberine has no effect on HDL cholesterol when compared with control or lifestyle interventions. (20579,34228,111363,111700,113462). Meta-analyses also show that berberine alone is similarly effective to statins at lowering lipid levels (100983,111362). Administration of berberine in combination with lipid-lowering drugs such as statins lowers total cholesterol by 10-15 mg/dL, LDL cholesterol by up to 9 mg/dL, and triglycerides by up to 30 mg/dL when compared with lipid-lowering drugs alone (91953,91956,99921,100983,111362). The dosage of berberine used most often in these studies was 500 mg twice daily, or 200-500 mg three times daily for 3-24 months. However, one meta-analysis suggests that berberine's effects on lipid levels may be transient, with significant improvements in total cholesterol, LDL cholesterol, and HDL cholesterol lacking in studies lasting 3 or more months (111362). Berberine has also been studied in combination with other supplements. Taking a combination product containing berberine 500 mg, policosanol 10 mg, and red yeast rice 200 mg daily for up to 12 months reduces total and LDL cholesterol levels when compared with placebo or ezetimibe 10 mg (34262,34283,34301). Taking another combination product (Armolipid Plus, Rottapharm S.p.A.) containing berberine, red yeast rice, policosanol, folic acid, coenzyme Q10, and astaxanthin daily for up to 12 months reduces total cholesterol by 10% to 13% and LDL cholesterol by 14% to 21%, and increases HDL cholesterol by 4% to 5% when compared with baseline or placebo. These effects are comparable to those seen with pravastatin 10 mg daily (89438,92142). It is unclear if the benefits of this combination product are due to berberine, other ingredients, or the combination. It is possible that the majority of the therapeutic effect is due to an ingredient in red yeast rice (monacolin K) that is identical to lovastatin.
• Hypertension. Berberine may have added benefits for reducing blood pressure when used in combination with amlodipine. Details: A meta-analysis shows that taking berberine 0.9 grams daily in combination with amlodipine for 2 months reduces systolic blood pressure by 5 mmHg and diastolic blood pressure by 2 mmHg when compared with amlodipine alone (91956).
• Polycystic ovary syndrome (PCOS). Berberine may improve some metabolic characteristics in women with PCOS and insulin resistance. It may also increase live births, although the data are conflicting. Details: Clinical research in patients with PCOS and insulin resistance shows that taking berberine 500-550 mg 2-3 times daily for 3 to 6 months reduces fasting plasma glucose, markers of insulin resistance, total cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, testosterone levels, body mass index, waist-to-hip ratio, acne severity, and markers of inflammation when compared with placebo or baseline. Berberine also seems to increase high-density lipoprotein (HDL) cholesterol and sex hormone binding globulin (SHBG) levels (34282,91952,111364). Lipid parameters also improved when compared with metformin, as did waist-to-hip ratio, body mass index, and SHBG levels in some, but not all, studies (34282,91952). The effect of berberine on ovulation, pregnancy, and birth rates in women with PCOS is unclear. A meta-analysis of several small, lower quality clinical studies conducted in China in patients with PCOS shows that taking berberine 900 mg daily in combination with other treatments, such as clomiphene or letrozole, for 3 to 6 months improves ovulation and clinical pregnancy rates when compared to medication therapy alone (115725). The validity of these findings is limited by heterogenous methods between clinical trials, including treatment combinations and duration. Additionally, the effect on birth rates was not evaluated. A clinical study, not included in the analysis above, shows that taking berberine 500 mg three times daily for three months prior to controlled ovarian stimulation increases the number of clinical pregnancies and live births by almost two-fold when compared with placebo. These effects are comparable to taking metformin 500 mg three times daily for 3 months (91952). However, other clinical research shows that taking a combination of berberine 1.5 grams daily and letrozole for ovarian stimulation does not increase live birth rates when compared with letrozole alone (97235).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Antipsychotic-induced metabolic side effects. It is unclear if oral berberine is beneficial in patients with antipsychotic-induced metabolic side effects. Details: A small clinical study in patients with schizophrenia who developed metabolic syndrome associated with antipsychotic therapy shows that taking berberine 300 mg twice daily for 12 weeks reduces body weight by 1.1 kg, body mass index (BMI) by 0.4 kg/m2, total cholesterol by 22 mg/dL, low-density lipoprotein (LDL) cholesterol by 20 mg/dL, and glycated hemoglobin (HbA1c) by 0.09% when compared with placebo (110103).
• Atrial fibrillation. Limited research suggests that oral berberine might prevent atrial fibrillation shortly after coronary artery bypass graft (CABG) surgery. Details: A small clinical study in Chinese patients who underwent CABG surgery shows that taking berberine 400 mg three times daily for 7 days reduces the risk of postoperative atrial fibrillation by 50% when compared with placebo (110106).
• Biliary disorders. It is unclear if oral berberine is beneficial in patients with biliary disorders. Details: A small clinical study in patients with primary sclerosing cholangitis shows that taking berberine ursodeoxycholate, an ionic salt formulation of berberine and ursodeoxycholic acid, 500-1000 mg twice daily for 6 weeks reduces levels of alkaline phosphatase (ALP), a marker of cholestasis and bile duct injury, when compared with placebo. ALP levels decreased by at least 50% in 7% and 17% of patients taking 500 mg and 1000 mg, respectively, compared with 0% of patients taking placebo (110105).
• Burns. Topical berberine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that topical treatment of second degree burns with an ointment containing berberine, beta-sitosterol, sesame oil, and other ingredients, applied every 4 hours for 20 days, is similar to conventional treatment with silver sulfadiazine cream (13526). It is unclear if this benefit is due to berberine, other ingredients, or the combination.
• Cardiovascular disease (CVD). It is unclear if berberine is beneficial in patients with CVD. Details: A meta-analysis of several small clinical studies in patients with atherosclerosis, ischemic stroke, or coronary heart disease shows that taking berberine alone does not improve lipid levels or markers of atherosclerosis but does reduce markers of inflammation when compared with routine therapy or statins. Additionally, the pooled analysis suggests that berberine reduces stroke severity, as measured by the NIH Stroke Scale, in patients with ischemic stroke (111362). This meta-analysis also shows that, when taken with a statin, berberine improves lipid levels, stroke severity, markers of atherosclerosis, and inflammatory markers when compared with statin therapy alone or routine treatment (111362). The validity of these findings is limited by the overall low-quality of the included studies, with unclear blinding and randomization; significant heterogeneity and differences in patient populations, berberine doses, and treatment durations studied; and concerns related to publication bias.
• Cholera. Although taking a single dose of berberine may be modestly beneficial for reducing stool volume, using berberine daily with tetracycline does not seem to provide added benefit. Details: Some preliminary clinical research shows that a single dose of berberine sulfate 400 mg decreases 24-hour stool volume by a small amount in subjects with cholera when compared with placebo (262). However, taking berberine 200-400 mg daily along with tetracycline 500 mg four times daily does not seem to further enhance the effects of tetracycline in treating cholera-induced diarrhea (34305,34306).
• Colorectal adenoma. Berberine may help prevent adenoma recurrence after polypectomy. Details: Preliminary clinical research in Chinese patients with colorectal adenomas who had undergone complete polypectomy shows that taking berberine 0.3 grams twice daily for 2 years reduces the risk of adenoma recurrence by 22% when compared with placebo (103197). A meta-analysis of this trial and two other small clinical studies in Chinese patients with a history of colorectal adenomas shows that taking berberine 0.1 grams three times daily for 18 months or 0.3 grams twice daily for 2 years reduces the risk of adenoma recurrence by 31% and 25% at years 1 and 2, respectively, when compared with placebo (110101). All available research has been conducted in China; it is unclear whether these results can be applied to other geographic locations.
• Congestive heart failure (CHF). Berberine may provide additional benefit to patients with CHF who are taking conventional medications. Details: Preliminary clinical research in patients with CHF secondary to ischemic or idiopathic dilated cardiomyopathy shows that adding berberine 1.2-2 grams daily for 8 weeks to conventional medications can reduce the frequency and complexity of premature ventricular contractions (PVCs) and reduce mortality when compared with placebo (13520).
• Coronary heart disease (CHD). Oral berberine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in statin-intolerant patients with coronary heart disease treated with a percutaneous intervention (PCI) shows that taking a specific combination product (Armolipid Plus, Rottapharm S.p.A.) containing berberine 500 mg, red yeast rice 200 mg, policosanol 10 mg, folic acid 0.2 mg, coenzyme Q10 2 mg, and astaxanthin 0.5 mg daily for 3 months reduces total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides, and increases high-density lipoprotein (HDL) cholesterol to a greater extent than ezetimibe 10 mg daily. Combining this specific product with either ezetimibe or a low-dose statin produces additional improvements in all lipid parameters after 3-12 months of treatment when compared with any of the agents alone (97232,97233). It is unclear if the benefits of this combination product are due to berberine, other ingredients, or the combination. Because red yeast rice contains a compound identical to lovastatin (monacolin K), it is likely that the cholesterol-lowering potential of this combination is mainly attributable to the red yeast rice constituent.
• Diarrhea. Limited data suggest that berberine may be helpful for diarrhea caused by bacteria. Details: Some preliminary clinical research shows that a single dose of berberine sulfate 400 mg decreases 24-hour stool volume in subjects with Escherichia coli-induced diarrhea when compared with placebo (262).
• Glaucoma. It is unclear if berberine is beneficial for glaucoma when used as an eye drop. Details: Preliminary clinical research shows that using eye drops containing berberine 2.5 mg and tetrahydrozoline 2.5 mg for 3 days does not reduce intraocular pressure in patients with open angle glaucoma when compared with eye drops containing tetrahydrozoline alone (34304).
• Hepatitis B. It is unclear if berberine is beneficial for improving liver function in people with hepatitis B. Details: Preliminary clinical research shows that taking berberine 1 gram daily for 2 months decreases blood glucose, triglycerides, and markers of liver damage, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in subjects with type 2 diabetes and hepatitis B when compared with control (34265).
• Hepatitis C. It is unclear if berberine is beneficial for improving liver function in people with this form of hepatitis. Details: Preliminary clinical research shows that taking berberine 1 gram daily for 2 months decreases blood glucose, triglycerides, and markers of liver damage, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in subjects with type 2 diabetes and hepatitis C when compared with control (34265).
• Impaired glucose tolerance (prediabetes). Small studies suggest that oral berberine may be beneficial in adults with prediabetes. Details: A very small clinical study in adults with overweight and prediabetes shows that taking berberine aqueous root extract (HIMABERB, Pharma Base S.A.) 500 mg 3 times daily for 12 weeks reduces fasting blood glucose by 15 mg/dL, glycated hemoglobin (HbA1c) by 0.7%, and 2-hour oral glucose tolerance test by 28 mg/dL and improves fasting insulin levels and measures of insulin resistance when compared with placebo (111699). The validity of these effects is limited by a very small sample size. Another small clinical study in adults with prediabetes shows that taking berberine phospholipids (Berbevis, Indena, SpA, Italy) 550 mg twice daily for 8 weeks reduces fasting blood glucose by 4 mg/dL and improves insulin levels when compared with placebo (111700).
• Irritable bowel syndrome (IBS). One small clinical study suggests that oral berberine may be beneficial in people with diarrhea-predominant IBS. Details: Preliminary clinical research shows that taking berberine 400 mg twice daily for 8 weeks in patients with diarrhea-predominant IBS reduces the frequency of diarrhea, abdominal pain, and defecation urgency when compared with placebo. Berberine may also improve overall symptom scores and IBS quality of life (97236). Observational research suggests that adding a supplement (Enterofytol PLUS, Tilman SA) providing berberine 200 mg and curcumin 42 mg orally twice daily for 2 months to conventional IBS treatment is associated with improvements in symptoms, such as abdominal discomfort, distension, and stool status, by up to 48% when compared with conventional treatment alone. Use of the supplement was also associated with a 64% reduced need for conventional treatments (113354). It is unclear if this effect is due to berberine, curcumin, or the combination.
• Menopausal symptoms. Oral berberine has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a combination of berberine plus soy isoflavones can reduce vasomotor symptoms in menopausal women when compared with taking calcium plus vitamin D (34287). It is not clear if this effect is due to berberine, soy isoflavones, or the combination.
• Metabolic dysfunction-associated steatotic liver disease (MASLD). It is unclear if oral berberine is beneficial in patients with MASLD. Details: A moderate-sized clinical study in adults with MASLD shows that taking berberine extract 500 mg orally three times daily for 12 weeks does not improve markers of liver damage or insulin resistance, fatty liver indices, or most lipid levels when compared with placebo (114769). Also review effectiveness in nonalcoholic fatty liver disease (NAFLD), a similar condition.
• Metabolic syndrome. Berberine may reduce some of the signs and symptoms of metabolic syndrome, but the evidence is weak. Details: Preliminary clinical research in adults with metabolic syndrome shows that taking berberine hydrochloride 500 mg three times daily before meals for 3 months reduces body mass index (BMI) by 0.6 kg/m2, systolic blood pressure (SBP) by 8 mmHg, triglycerides by 18 mg/dL, and serum glucose levels by 2 mg/dL, and can also improve insulin sensitivity, when compared with baseline (91957). The validity of these findings is limited by the lack of a control group. Other preliminary clinical research shows that taking a combination product (Armolipid Plus, Rottapharm S.p.A.) containing berberine 500 mg, red yeast rice 200 mg, policosanol 10 mg, folic acid 0.2 mg, coenzyme Q10 2 mg, and astaxanthin 0.5 mg daily for 18 weeks improves SBP, left ventricular mass, and flow-mediated dilation in patients with metabolic syndrome when compared with control (34289). It is not clear if this effect is due to berberine, the other ingredients, or the combination.
• Nonalcoholic fatty liver disease (NAFLD). Oral berberine may improve some measures of liver function and blood lipids in people with NAFLD. Details: A meta-analysis of clinical studies and preliminary clinical research in patients with NAFLD, some with comorbid type 2 diabetes, show that taking berberine 600 mg to 6.35 grams daily, alone or in combination with metformin or lifestyle interventions, for 7 to 22 weeks reduces markers of liver damage, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutamyl transpeptidase (GGT) and improves body mass index (BMI), measures of insulin resistance, and most lipid parameters when compared with control and baseline (34286,113462). Other preliminary clinical research shows that taking berberine 500 mg three times daily for 16 weeks reduces hepatic fat content by 21% when compared with lifestyle modification. Berberine also seems to reduce hepatic fat content, AST, and ALT similarly to pioglitazone 15 mg daily, while reducing body weight, body mass index, and total cholesterol more than pioglitazone (97237). Also review effectiveness in metabolic dysfunction-associated steatotic liver disease (MASLD), a similar condition.
• Obesity. It is unclear if oral berberine is beneficial in patients with obesity. Details: A meta-analysis of 12 small clinical studies, most in patients with various metabolic conditions, shows that taking berberine 300-1500 mg daily for up to 24 months reduces body weight by around 2 kg, body mass index (BMI) by 0.5 kg/m2, and waist circumference by about 1 cm when compared with a control group (104508). However, most of the studies are small, of varying quality, with significant heterogeneity, and likely inadequately powered to detect significant changes. Additionally, none of the studies required patients to have overweight or obesity for inclusion.
• Radiation-induced diarrhea. One small study suggests that oral berberine may reduce diarrhea associated with radiation-induced intestinal damage. Details: Preliminary clinical research shows that taking berberine 300 mg three times daily for 2 weeks can reduce the frequency and severity of radiation-induced intestinal damage and diarrhea in patients receiving abdominal or pelvic radiation therapy when compared with placebo (34263).
• Radiation fibrosis. It is unclear if oral berberine is beneficial for reducing radiation-induced lung damage. Details: Preliminary clinical research shows that taking berberine 20 mg/kg once daily for 6 weeks during radiation therapy reduces the incidence of radiation-induced lung injury and improves lung function in patients treated for NSCLC when compared with placebo (34253).
• Stroke. It is unclear if oral berberine is beneficial in adults with acute ischemic stroke. Details: A meta-analysis of several small clinical studies in adults with acute ischemic stroke shows that taking berberine 0.3-1.0 grams daily for up to 6 months in addition to conventional therapy reduces stroke severity, as measured by the NIH Stroke Scale, improves markers of atherosclerosis and inflammation, and reduces triglycerides and low-density lipoprotein cholesterol when compared with routine therapy as control (111698). The validity of these findings is limited by the overall low quality of the included studies, with unclear blinding and randomization. Other limitations include significant heterogeneity in patient populations, berberine doses, and treatment durations studied.
• Thrombocytopenia. It is unclear if oral berberine is beneficial for improving platelet counts in people with this condition. Details: Preliminary clinical research shows that taking berberine bisulfate 5 mg three times daily before meals for 15 days, either alone or with prednisolone, can increase platelet count in patients with primary or secondary thrombocytopenia when compared with baseline (34317).
• Trachoma. It is unclear if berberine is beneficial for trachoma when administered as eye drops. Details: Preliminary clinical research shows that berberine ophthalmic solution might be useful for treating trachoma, a common cause of blindness in developing countries. Solutions of 0.2% berberine have been applied three times daily for 3-12 weeks, or solutions of 0.5% three times daily for 1-3 weeks (13523,34303,34310,34313).
• Ulcerative colitis. It is unclear if oral or rectal berberine is beneficial for ulcerative colitis. Details: A meta-analysis of several small, lower quality clinical studies in adults with ulcerative colitis shows that taking berberine orally (600-900 mg daily) or rectally (4-6 grams daily) for 3-12 weeks, in addition to mesalamine, improves the rate of patients with complete remission or reduced symptoms, such as bowel movements, blood in stools, or abdominal pain, when compared to mesalamine alone (115724). The validity of these findings is limited by heterogenous methods between clinical trials, including route of administration and treatment duration.
• Ventricular arrhythmias. Limited research suggests that oral berberine might lower the frequency of premature ventricular contractions (PVCs). Details: Data from a meta-analysis of 10 small clinical trials, all conducted in China, shows that taking oral berberine, 0.3-0.6 grams 3 or 4 times daily for 7-30 days has a similar efficacy rate to antiarrhythmic drugs, and a lower incidence of adverse effects, in the management of PVCs. A combination of berberine and antiarrhythmic drugs has a higher efficacy rate and similar adverse effect rate, when compared with antiarrhythmic drugs alone (112947). The quality of this evidence is low. More evidence is needed to rate berberine for these uses.

(Read more about BERBERINE)

LIKELY EFFECTIVE

• Coenzyme Q10 deficiency. Taking coenzyme Q10 orally improves symptomatic deficiency. Details: Rare cases of acquired coenzyme Q10 deficiency with symptoms of weakness, fatigue, and seizures have been reported (8160,8161). In adults, deficiency can be treated with coenzyme Q10 orally, 150-2400 mg daily in up to three divided doses. In children, 30 mg/kg, or 60-250 mg daily in up to three divided doses has been used (8160,8161,89417). Data from several multinational disease registries has also evaluated the use of coenzyme Q10 in patients with primary coenzyme Q10 deficiency, a rare genetic disorder. This data indicates that patients who take coenzyme Q10 supplements have a mean reduction of 88% in proteinuria at 12 months when compared with patients who do not take coenzyme Q10. In patients under 18 years of age with primary deficiency and chronic kidney disease at baseline, taking coenzyme Q10 supplements is associated with a 5-year survival without kidney failure of 62%, compared with 19% for those not taking coenzyme Q10 (108956).

POSSIBLY EFFECTIVE

• Congestive heart failure (CHF). Oral coenzyme Q10 may provide benefit to patients with CHF by improving some, but not all, measures of disease severity when given in combination with conventional therapy. Details: Population research has found that CHF is associated with low coenzyme Q10 levels that correlate with severity of disease, and may be a predictor of mortality risk (44059,44220). Meta-analyses of lower-to-moderate quality clinical studies in adults with heart failure, mostly heart failure with reduced ejection fraction, show that taking coenzyme Q10 30-400 mg daily reduces the relative risk of mortality and hospitalization, and modestly improves exercise capacity when compared with control and placebo. The validity of these results is limited by the heterogenous methods across clinical studies including heart failure classification, dose, duration, concurrent therapy, variable measures of treatment effect, and short follow-up (108954,115943,115946). Other clinical research shows that adding oral coenzyme Q10 seems to improve quality of life and decrease symptoms of CHF such as dyspnea, peripheral edema, enlarged liver, and insomnia in patients with mild to severe (New York Heart Association (NYHA) class II-IV) CHF (6037,6038,6407,6408,6409,8909,12170,43967,43971,44042)(44277,44288,44289,44304,44334,44352,96542). Additional clinical research shows that taking coenzyme Q10 30 mg daily for 1 year in addition to standard care reduces the incidence of atrial fibrillation by about 73% when compared with standard care alone in patients with NYHA class II-IV CHF (95609). However, not all evidence is positive. Some research suggests that coenzyme Q10 does not improve objective measures of CHF, including left ventricular ejection fraction (LVEF), cardiac output, or NYHA classification (5090,5248,6037,6038,43904,43932,96542,97902). It is possible that the benefit of coenzyme Q10 depends on the dose and duration, the severity of CHF, and the specific conventional therapies taken concurrently (43973). In patients with CHF with preserved ejection fraction (HFpEF) and LVEF of 50% or greater, taking coenzyme Q10 600 mg daily for 12 weeks reduces B-type natriuretic peptide levels and improves Kansas City Cardiomyopathy Questionnaire (KCCQ) scores, level of vigor, and LVEF when compared with placebo (108959).
• Diabetic neuropathy. When taken alone or as add-on treatment with pregabalin, most research suggests that oral coenzyme Q10 reduces symptoms in patients with diabetes and neuropathy. Details: Clinical research shows that taking coenzyme Q10 400 mg orally daily for 12 weeks significantly improves nerve conduction and symptoms of neuropathic pain when compared with placebo in diabetic patients with polyneuropathy (44217). The beneficial effects of coenzyme Q10 have also been investigated as an add-on treatment in patients taking pregabalin 150 mg daily. Clinical research shows that taking coenzyme Q10 100 mg three times daily for 8 weeks reduces pain severity and sleep interference due to pain when compared with placebo. The proportion of patients taking coenzyme Q10 with a decline in pain of at least 50% was 47%, compared with 27% of those taking placebo. Despite these findings, there was no difference in patient global improvement (109391). However, some research disagrees. One clinical trial shows that taking coenzyme Q10 (Health Burst) 200 mg daily for 12 weeks does not affect neuropathic symptoms, including pain, sensations, and strength, when compared with placebo (109386).
• Fibromyalgia. Oral coenzyme Q10 seems to improve both physical and psychological symptoms of this condition. Details: Clinical research in women with fibromyalgia shows that taking coenzyme Q10 300-400 mg orally daily for 40 days to 3 months improves pain by 24% to 56%, fatigue by 22% to 47%, sleep disturbances by 33%, morning tiredness by 56%, and tender points by 44% when compared with placebo. Patients also experience an improvement in psychological symptoms, including depression and anxiety (89416,97912,97913).
• Ischemia-reperfusion injury. Oral or intravenous coenzyme Q10 may help reduce hypoxic damage during cardiac bypass or vascular surgery. Details: Clinical research shows that taking coenzyme Q10, 150-300 mg orally daily in up to 3 divided doses for 1-2 weeks before cardiac bypass or vascular surgery, or 5 mg/kg IV two hours prior to surgery, reduces hypoxic damage during the surgery (11902,11903,44031,44294). However, coenzyme Q10 has no effect on cardiac function or troponin levels (11904,44292).
• Migraine headache. The American Academy of Neurology considers oral coenzyme Q10 to be possibly effective for migraine prevention in adults. Its benefit in children is unclear. Details: Meta-analyses of small clinical studies in adults show that coenzyme Q10 reduces migraine frequency and severity (105070,115730). For example, a meta-analysis of 6 small clinical trials in adults shows that taking coenzyme Q10 100-400 mg daily reduces the average number of migraine attacks by 1.7 per month, reduces duration of migraines by approximately 1.7 hours, and modestly reduces severity when compared with placebo. Furthermore, reductions in migraine frequency, duration, and severity are dose-dependent (115730). The validity of these results is limited by heterogeneity across clinical studies. Data from small open-label, non-randomized clinical trials in adults show it can take up to 3 months to see benefit of coenzyme Q10 in reducing frequency of migraine headache (8135,95608). In children and adolescents, some clinical research shows that taking coenzyme Q10 orally, as 100 mg daily or 1-3 mg/kg daily, for 12-16 weeks does not improve headache frequency, severity, or duration when compared with placebo. However, it may reduce migraine frequency in children with low coenzyme Q10 levels (15256,44197). However, another clinical study shows that taking coenzyme Q10 daily is less effective than amitriptyline after one month, but as effective after 3 months, for improving headache frequency, severity, or duration, as well as quality of life. In this study, the dose of coenzyme Q10 was based on weight; 30 mg daily for children weighing less than 30 kg and 60 mg daily for children weighing at least 30 kg (109388).
• Multiple sclerosis (MS). Oral coenzyme Q10 seems to reduce fatigue and depression associated with MS. Details: Clinical research shows that taking coenzyme Q10 500 mg orally daily for 3 months reduces fatigue and depression in patients with MS when compared with placebo (96539).
• Muscular dystrophy. Oral coenzyme Q10 seems to improve physical performance in patients with muscular dystrophy of various forms. Details: Two small clinical studies show that taking coenzyme Q10 orally 100 mg daily for 3 months seems to improve physical performance when compared with placebo in some patients with various muscular dystrophies (2127).
• Myocardial infarction (MI). Oral coenzyme Q10 seems to reduce cardiac events and improve survival in patients who have had an MI. It is unclear if coenzyme Q10 improves survival in patients after cardiac arrest. Details: One small clinical study in patients with acute MI shows that starting coenzyme Q10 60 mg twice daily within 72 hours of the MI appears to significantly reduce the risk of cardiac events, including non-fatal MI and cardiac death, by 52% when administered for 28 days and by 45% when administered for up to one year (10152,44330). Also, a small clinical study in patients with recent MI who received cardiopulmonary resuscitation, shows that administering a 250 mg loading dose of coenzyme Q10 solution followed by 150 mg three times daily through a nasogastric tube for 5 days improves the 3-month survival rate by 134% when compared with placebo (43935). However, another clinical study in a similar patient population conducted to replicate these results shows that administering coenzyme Q10 300 mg in 50 mL of Ensure every 12 hours for 7 days does not improve in-hospital mortality or neurological outcomes when compared with placebo (105068).
• Peyronie disease. Coenzyme Q10 taken orally may reduce Peyronie disease severity. Details: Clinical research shows that, in patients with early chronic Peyronie disease, taking coenzyme Q10 (Kaneka Nutrients, Osaka) 300 mg orally daily for 24 weeks reduces new plaque formation and plaque size and improves erectile function when compared with placebo. Additionally, disease progression is slowed in about 76% of patients (44180).

POSSIBLY INEFFECTIVE

• Alzheimer disease. Coenzyme Q10 appears to be ineffective for improving cognition. Details: One clinical study shows that taking coenzyme Q10 1200 mg orally daily for 16 weeks does not improve cognition scores when compared with placebo in patients with Alzheimer disease (19206).
• Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease). Oral coenzyme Q10 does not attenuate functional decline in ALS patients. Details: Clinical research shows that taking coenzyme Q10 2700 mg orally daily for 9 months does not significantly attenuate a decline in ALS functioning scores when compared with placebo (44131). Higher doses, up to 3000 mg daily, have been tolerated by patients with ALS for 5 months, although the effect on ALS functioning at this dose is not known (43955).
• Chemotherapy-related fatigue. Oral coenzyme Q10 does not seem to help with fatigue due to chemotherapy. Details: Clinical research shows that taking coenzyme Q10 100 mg orally three times daily for 24 weeks does not reduce chemotherapy-related fatigue or improve quality of life when compared with placebo in breast cancer patients undergoing chemotherapy with or without radiation (89420).
• Diabetes. Most clinical research does not show any benefit with oral coenzyme Q10 in patients with type 1 or type 2 diabetes. However, some research suggests a possible benefit on insulin resistance. Details: Although a recent meta-analysis and some individual clinical research shows that coenzyme Q10 modestly reduces fasting glucose levels and glycated hemoglobin (HbA1c) in patients with type 1 or type 2 diabetes, most clinical research shows that coenzyme Q10 has no clinically meaningful effect on these parameters (456,492,2126,9890,11877,17704,44023,96544,97911,97918)(99636,103778,109389). However, a recent meta-analysis in patients with type 1 or type 2 diabetes shows that improvements in insulin resistance may be clinically meaningful when compared with placebo (109389). In people with type 2 diabetes and nephropathy requiring hemodialysis, coenzyme Q10 120 mg orally daily for 12 weeks does not improve blood glucose levels, HbA1c, or lipid levels when compared with placebo, although it is associated with a decrease in serum insulin levels and insulin resistance (99636).
• Parkinson disease. Most clinical research does not show any benefit with the use of oral coenzyme Q10 in patients with Parkinson disease. Details: While some conflicting evidence exists (8938,15255), a large clinical trial and a meta-analysis of 8 small clinical studies in patients with Parkinson disease show that taking coenzyme Q10 300-2400 mg daily for up to 2 years does not improve Parkinson disease symptoms at any stage of the disease, or slow progression of the disease, when compared with placebo (89421,95610). In addition, a clinical study in patients with mid-stage Parkinson disease shows that taking a specific nanoparticulate coenzyme Q10 supplement (Nanoquinon, MSE Pharmazeutilka) 100 mg orally three times daily does not reduce symptoms when compared with placebo (15395).
• Post-polio syndrome. Muscle function in people with post-polio syndrome is not improved by oral coenzyme Q10. Details: Clinical research shows that taking coenzyme Q10 100 mg twice daily for 12 weeks does not improve muscle strength when compared with baseline, nor does it improve muscle function or muscle endurance when compared with placebo, in patients with post-polio syndrome (44054). Other clinical research shows that taking coenzyme Q10 100 mg daily for 60 days does not improve levels of fatigue when compared with placebo in patients with post-polio syndrome (97917).

LIKELY INEFFECTIVE

• Athletic performance. There is some evidence that exercise can deplete coenzyme Q10 and that supplementation will prevent this depletion. However, there is no evidence that taking coenzyme Q10 is beneficial. Details: Clinical research shows that taking coenzyme Q10 orally does not improve aerobic or anaerobic power or perceived exertion in athletes and non-athletes (2109,2110,8911,44122,44227). While some evidence suggests coenzyme Q10 slightly improves tolerance to higher workloads, more research is needed to tell if coenzyme Q10 is effective for this purpose (8911). One clinical study shows that taking coenzyme Q10 300 mg orally daily for 8 days reduces exercise-induced fatigue when compared with placebo (44006); other research shows that doses of 100-200 mg do not have this effect (44122,44233,44299). Taking the ubiquinol form of coenzyme Q10 200 mg orally daily for one month prevents exercise-induced coenzyme Q10 depletion and decreases levels of reactive oxygen species in blood mononuclear cells in young male athletes performing an intense long-distance run. However, it does not affect physical performance or markers of muscle damage (99429).
• Huntington disease. The ubiquinol form of coenzyme Q10 does not seem to improve function in people with this condition. Details: Ubiquinol, a reduced form of coenzyme Q10, has been evaluated for use in Huntington disease (11873). However, a large, high-quality study shows that taking coenzyme Q10 2.4 grams orally daily for up to 5 years does not slow the progression or functional decline in patients with Huntington disease (96538). Other studies using doses up to 600 mg daily also show no benefit (1357,8940).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related macular degeneration (AMD). Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in adults with early AMD shows that taking a specific combination product (Phototrop, Sigma-tau Health Science Ltd.) containing coenzyme Q10 10 mg, acetyl-L-carnitine 100 mg, and omega-3 fatty acids 530 mg orally daily for 12 months seems to reduce the percentage of patients who experience deterioration of vision by about 50%, and the percentage who have reduced light sensitivity by about 39%, when compared with placebo (43946). The effects of coenzyme Q10 alone are unclear.
• Aging. Although there has been interest in using oral coenzyme Q10 for aging, there is insufficient reliable information about the clinical effects of coenzyme Q10 for this purpose.
• Angina. There is some limited clinical evidence that coenzyme Q10 can improve exercise tolerance and symptoms in people with this condition. Details: Preliminary clinical research shows that taking coenzyme Q10 50 mg three times daily orally for 4 weeks improves exercise tolerance in people with angina by about 18% (2121). Also, taking 60 mg once daily for 4 weeks improves heart failure scores, angina symptoms, and heart volume when compared to baseline in patients with stable angina (44336). The validity of these findings is limited by the lack of a comparator group.
• Anthracycline cardiotoxicity. Evidence on the use of coenzyme Q10 to protect against anthracycline cardiotoxicity in adults and children is conflicting. Details: Preliminary clinical research in children aged 3-12 years shows that taking coenzyme Q10 orally 100 mg twice daily might protect against anthracycline cardiotoxicity (44279). However, evidence from larger clinical trials evaluating patients aged 16-77 years is conflicting. Results from one of these studies suggests that intravenous administration of coenzyme Q10 1 mg/kg daily the day before, the day of, and for 2 days after anthracycline treatment does not protect against cardiotoxicity (44267). Differences between the studies may be due to methodological problems, or differences in doses, route of administration, and age of participants.
• Asthma. Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking a combination of coenzyme Q10 (Q-Gel, Tishcon Corporation) 120 mg, vitamin E 400 mg, and vitamin C 250 mg orally daily in addition to conventional anti-asthmatic therapy for 16 weeks might reduce the dosage of corticosteroids required by patients with mild to moderate asthma. However, it does not appear to improve lung function any more than standard therapy alone (43969).
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral coenzyme Q10 is beneficial in children with ADHD. Details: A small clinical study in children aged 6-16 years with ADHD who are unresponsive to atomoxetine therapy shows that taking coenzyme Q10 1-3 mg/kg with atomoxetine 0.5-1.8 mg/kg daily for 6 months improves parent-rated symptoms of ADHD, particularly hyperactivity-related symptoms, when compared with placebo plus atomoxetine (107449).
• Autism spectrum disorder. It is unclear if the ubiquinol form of coenzyme Q10 taken orally is beneficial in children aged 3-6 years with this condition. Details: A small clinical study in children aged 3-6 years suggests that taking the reduced form of coenzyme Q10, ubiquinol (Li-QH, Tishcon Corporation), 50 mg orally once daily for one week followed by 50 mg twice daily for 11 weeks, improves symptoms of autism spectrum disorder, including communication with parents, ability to play with friends, verbal communication, sleeping, food rejection, aggressiveness, and self-harm, when compared with baseline, per parent assessment (89419). The validity of these findings is limited by the small study size, the use of parent assessment, and the lack of a comparator group.
• Benign prostatic hyperplasia (BPH). Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical trial in patients with BPH shows that taking coenzyme Q10 100 mg plus L-carnitine daily for 8 weeks modestly decreases prostate volume and improves sexual performance when compared with placebo. There was no effect on prostate symptoms, prostate specific antigen levels, or quality of life. All patients were also taking finasteride 5 mg daily (113226). It is unclear if these effects are due to coenzyme Q10, L-carnitine, or the combination.
• Bipolar disorder. It is unclear if oral coenzyme Q10 is beneficial for bipolar disorder in older adults. Details: Preliminary clinical research in people 55 years of age or older with bipolar disorder shows that taking coenzyme Q10 800 mg orally daily for 4 weeks improves symptoms of depression when compared with baseline (95606). The validity of this finding is limited by the lack of a comparator group.
• Breast cancer. Low coenzyme Q10 levels may be associated with an increased risk of breast cancer. The benefit of coenzyme Q10 supplementation is unclear. Details: Population research in Chinese women has found that low plasma coenzyme Q10 levels are associated with an increased risk of breast cancer (44194).
• Burns. It is unclear if oral coenzyme Q10 is beneficial for burns. Details: A small clinical study in patients with burns covering 20% to 60% of their body surface area shows that taking coenzyme Q10 300 mg daily for 10 days does not improve length of intensive care stay or mortality when compared with placebo (114555). However, this study may not have been adequately powered to detect a difference between groups.
• Cancer. Low coenzyme Q10 levels may increase the risk of cancer development and progression. Details: Population research has found that low coenzyme Q10 levels are associated with increased risk of metastatic melanoma (43959). Preliminary clinical research suggests that taking coenzyme Q10 150 mg twice daily along with vitamins A, C, and E, selenomethionine, beta-carotene, and folic acid extends survival time by 40% when compared with predicted survival in patients with end-stage cancer from various different primary sites (44159). It is unclear if this effect is due to coenzyme Q10, other ingredients, or the combination.
• Cardiovascular disease (CVD). It is unclear whether oral coenzyme Q10 has a role in preventing complications from CVD. Details: Preliminary clinical research shows that taking coenzyme Q10 300 mg 2 hours prior to an elective percutaneous coronary intervention does not reduce periprocedural myocardial injury or prevent major adverse cardiac events during one month of follow-up (96543). Other clinical research shows that taking a combination of coenzyme Q10 (Bio-Quinon, Pharma Nord) 100 mg twice daily plus organic selenium yeast tablets (SelenoPrecise, Pharma Nord) 200 mcg daily for 4-5 years reduces the risk of death from CVD by 7% when compared with placebo in elderly people living in Sweden (92904). This benefit appears to persist even after supplement discontinuation, with an 18% reduction at 10 years and an 11% reduction at 12 years (96546,97466,97906). In this same trial, post-hoc subgroup analyses in patients with elevated baseline D-dimer levels and/or hypertension or ischemic heart disease shows that taking this combination reduces cardiovascular mortality when compared with placebo (105874). It is unclear if these benefits are due to coenzyme Q10, selenium, or the combination.
• Cataracts. It is unclear if coenzyme Q10-containing eye drops are beneficial in patients undergoing cataract surgery. Details: Clinical research suggests that administering an ophthalmic solution containing coenzyme Q10 and vitamin E D-alpha-tocopheryl polyethylene glycol 1000 succinate twice daily for 9 months increases the speed of nerve regeneration when compared with saline solution in post-cataract surgery patients (44228).
• Cerebellar ataxia. It is unclear if coenzyme Q10 is beneficial for this condition. Details: Preliminary clinical research in patients with cerebellar ataxia shows that coenzyme Q10 30 mg/kg daily for 2 years improves ataxia scores by 48%, posture scores by 63%, and kinetic function scores by 37% when compared with baseline, but only in patients who are coenzyme Q10 deficient (44177). The validity of these findings is limited by the lack of a comparator group.
• Chronic fatigue syndrome (CFS). Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients with CFS shows that taking coenzyme Q10 200 mg plus NADH 20 mg daily for 8 weeks does not improve measures of fatigue, sleep, or quality of life when compared with placebo (107448).
• Chronic obstructive pulmonary disease (COPD). It is unclear if coenzyme Q10 is beneficial for improving exercise tolerance in people with COPD. Details: Preliminary clinical research suggests that taking coenzyme Q10 90 mg daily for 8 weeks reduces lactate production during anaerobic exercise in people with COPD, but does not improve oxygen consumption or exercise performance, when compared with baseline (44293). The validity of these findings is limited by the lack of a comparator group.
• Cocaine dependence. Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One clinical study in patients with cocaine dependence shows that taking a combination of coenzyme Q10 200 mg and L-carnitine 500 mg orally daily for 8 weeks does not reduce cocaine use when compared with placebo, as measured by urine benzoylecgonine levels and self-reported usage (43940).
• Coronavirus disease 2019 (COVID-19). It is unclear if oral coenzyme Q10 is beneficial for patients exposed to COVID-19 or for those with persistent symptoms after COVID-19 infection. Details: A small, non-randomized, open-label study in adults exposed to COVID-19 shows that taking 20 mg of a specific coenzyme Q10 product daily for 14 days postexposure reduces positive COVID-19 testing by 45% and duration of symptoms by 2 days when compared with no intervention (114558). The validity of these findings is limited by the exploratory nature of the study. Clinical research in individuals with previously confirmed COVID-19 infection and continued symptoms lasting more than 12 weeks shows that taking coenzyme Q10 (Pharma Nord) 100 mg five times daily for 6 weeks does not reduce the number or severity of symptoms when compared with placebo. The most common symptoms were concentration problems, mental and physical fatigue, headache, and/or muscle weakness (109392).
• Critical illness (trauma). It is unclear if oral coenzyme Q10 is beneficial in patients hospitalized due to acute trauma. Details: Preliminary clinical research in patients who are mechanically ventilated due to acute trauma and have low baseline coenzyme Q10 plasma levels shows that taking sublingual coenzyme Q10 (Nutri Q10, Nutri Century) 400 mg daily for 7 days reduces the duration of intensive care stay, mechanical ventilation, and hospitalization by 4 days, 2 days, and 6 days, respectively, when compared with placebo. Patients taking coenzyme Q10 also demonstrated larger improvements in organ function scores and coma scores than those taking placebo (105875).
• Cyclic vomiting syndrome (CVS). Limited evidence suggests oral coenzyme Q10 may reduce episodes of CVS. Details: Preliminary clinical research shows that taking coenzyme Q10 10 mg/kg/day is comparable to amitriptyline 0.5-1 mg/kg/day for reducing the number of CVS episodes in both children and adults (17703). Guidelines published by the American Neurogastroenterology and Motility Society and the Cyclic Vomiting Association provide a conditional recommendation for the use of coenzyme Q10 as prophylactic therapy for adults in the treatment of CVS based on very-low quality evidence (115640).
• Diabetic nephropathy. Although there has been interest in using oral coenzyme Q10 for diabetic nephropathy, there is insufficient reliable information about the clinical effects of coenzyme Q10 for this purpose.
• Dilated cardiomyopathy. Very small clinical studies suggest that children and adolescents with dilated cardiomyopathy may benefit from oral coenzyme Q10. Details: Preliminary clinical research in children with dilated cardiomyopathy suggests that taking coenzyme Q10 3-10 mg/kg daily, divided into 2-3 doses for up to 9 months, improves ejection fraction and New York Heart Association (NYHA) classification when compared to baseline (12199,13223). Also, in people under 20 years of age, taking a specific oral liquid formulation of coenzyme Q10 (QuinoMit Q10 Fluid, MSE Pharmazeutika GmbH), 10 mg/kg daily for 24 weeks produces a small increase in ejection fraction and improves NYHA class from II to I in 30% of patients (99427). The validity of these findings is limited by the lack of comparator groups.
• Depression. It is unclear if oral coenzyme Q10 is beneficial for depression. Details: A clinical study in patients in Iran with moderate to severe depression shows that taking coenzyme Q10 200 mg daily for 8 weeks in addition to an antidepressant modestly improves depression scores when compared with placebo added to an antidepressant (114557).
• Dry eye. Ophthalmic coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research has evaluated the use of a specific eye drop (VisuXL, Visufarma) containing coenzyme Q10 and cross-linked hyaluronic acid, in a 1:1 ratio with alpha-tocopherol polyethylene glycol succinate. One study in menopausal women receiving antidepressants shows that placing 1 drop in each eye twice daily for 8 weeks reduces dry eye severity by 17% and improves tear break-up time when compared to 5 drops daily of carmellose eye drops (104553). In addition, another study in adults with mild to moderate dry eye shows that placing 1 drop in each eye four times daily for 12 weeks reduces dry eye severity by 14% and decreases some laboratory markers of dry eye when compared to hyaluronic acid alone. Both groups demonstrated similar improvement in meibomian gland function and tear break-up time (97909). The effect of coenzyme Q10 when used alone is unclear.
• Dry mouth. It is unclear if oral ubiquinol or ubiquinone improves salivary secretion. Details: Preliminary clinical research suggests that taking coenzyme Q10, as the reduced ubiquinol form or as the oxidized ubiquinone form, 100 mg orally daily for one month, improves salivary secretion by 72% to 82% when compared with baseline in patients with dry mouth (44191). The validity of these findings is limited by the lack of a comparator group.
• Erectile dysfunction (ED). It is unclear if oral coenzyme Q10 is beneficial in patients with ED. Details: A small, open-label study in patients with hypertension and complaints of ED shows that taking coenzyme Q10 200 mg daily for 3 months along with current antihypertensive therapy does not improve symptoms of ED when compared with antihypertensive therapy alone (107447).
• Fatigue. It is unclear if oral coenzyme Q10 is beneficial for reducing fatigue. Details: A meta-analysis of low- to moderate-quality clinical research in mixed populations shows that taking coenzyme Q10 modestly reduces feelings of fatigue when compared with placebo. This improvement was consistent between groups of healthy individuals and individuals with fatigue related to disease. However, a sub-group analysis shows that benefits are limited to studies in which coenzyme Q10 was studied as a single ingredient. Doses of coenzyme Q10 ranged from 60 mg to 500 mg daily for 4-12 weeks with treatment effects appearing to be both dose- and duration-dependent (109387).
• Friedreich ataxia. Oral coenzyme Q10 has been evaluated in combination with vitamin E; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking coenzyme Q10 (Bio-Quinon Q10, Pharma Nord) 200 mg orally twice daily plus vitamin E (Bio-E-Vitamin, Pharma Nord) 1050 IU twice daily for 47 months improves measures of cardiovascular function by 20% when compared with baseline. However, it does not improve posture or gait, or prevent deterioration of posture, gait, speech, or eye function, when compared with baseline (43943,44064). It is unclear if these benefits are due to coenzyme Q10, vitamin E, or the combination. Also, the validity of these findings is limited by the lack of a comparator group.
• Hearing loss. There is conflicting evidence regarding the effects of oral coenzyme Q10 on hearing loss of various etiologies. Details: Some clinical research shows that taking coenzyme Q10 terclatrate (Qter), a water-soluble formulation of coenzyme Q10, 160 mg orally daily for 30 days improves hearing thresholds when compared to baseline in patients with age-related hearing loss (44171,44184). However, taking coenzyme Q10 terclatrate 200 mg daily for 7 days does not significantly improve hearing thresholds when compared with placebo in patients with noise-induced hearing loss (44143). Also, combining coenzyme Q10 with conventional steroid therapy for 2 weeks does not improve hearing when compared with steroid therapy alone in patients with sudden sensorineural hearing loss (44185).
• Hepatitis C. It is unclear if oral coenzyme Q10 is beneficial in patients with this condition. Details: Clinical research shows that taking coenzyme Q10 up to 80 mg orally daily for 28 days does not reduce serum liver enzymes when compared with placebo in patients with chronic hepatitis C who are unresponsive to conventional treatment (44172).
• Hyperlipidemia. There is conflicting evidence regarding the effects of coenzyme Q10 on cholesterol levels in adults. However, any changes are unlikely to be clinically meaningful. Details: A meta-analysis of 50 moderate-quality clinical trials shows that taking coenzyme Q10 has small beneficial effects on levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides when compared with a control, usually placebo (109394). However, whether coenzyme Q10 produces clinically meaningful changes is unclear. In a subgroup of patients with dyslipidemia, coenzyme Q10 does not seem to have significant beneficial effects on total cholesterol (109394). Also, previous individual clinical trials and meta-analyses in specific populations, including studies in which lipoprotein A was measured, as well as populations with diabetes, coronary artery disease, and others, have not shown beneficial effects on plasma lipids (17704,44187,96545,97918,109394). The effect of coenzyme Q10 on lipoprotein A has also been investigated. Individual studies and a meta-analysis show that taking coenzyme Q10 slightly reduces plasma levels of lipoprotein A when compared with placebo (17704,44187,96545). Most studies have used doses of 100-500 mg daily for 4-24 weeks (17704,44187,96545,96547,97910,109394). Coenzyme Q10 has also been studied in combination with other ingredients. A moderate-sized, open-label clinical study in adults with mild hypercholesterolemia and low cardiovascular disease risk shows that taking a combination product containing coenzyme Q10 2 mg, red yeast rice, grape seed extract, olive tree leaf extract, and B vitamins (Arichol, Epsilon Health) daily for 8 weeks reduces total cholesterol and LDL cholesterol, but not HDL cholesterol or triglycerides, when compared with placebo (111559). The validity of this effect is limited by a lack of blinding. It is unclear if this effect is due to coenzyme Q10, other ingredients, or the combination.
• Hypertension. Most research suggests that oral coenzyme Q10 may reduce systolic blood pressure (SBP), but not diastolic blood pressure (DBP). Details: Most clinical research shows that taking coenzyme Q10 100-900 mg orally daily in divided doses, either alone or with conventional medications, for up to 12 weeks significantly lowers SBP (2122,3365,9890,17650,17651,17702,44343,109393). One meta-analysis of moderate quality clinical research in patients with cardiometabolic disorders shows that supplementation with coenzyme Q10, especially 100-200 mg daily for at least 12 weeks, reduces SBP by 5 mmHg (109393). However, some studies show conflicting results. Most clinical research shows that coenzyme Q10 supplementation does not reduce DBP (8907,96541,109393). Also, a meta-analysis of two clinical studies (17651,44211) shows that taking coenzyme Q10 100-200 mg orally daily has no significant effect on blood pressure when compared with placebo (95607). Conflicting results may be due to differences in the severity of hypertension at baseline, adjustments made to conventional medications during studies, and the presence of a variety of concomitant conditions. Some data also suggest that effects may be greater in people with low baseline levels of coenzyme Q10 (2122,17650,17651).
• Hypertrophic cardiomyopathy. It is unclear if oral coenzyme Q10 is beneficial for this condition. Details: A very small clinical study of 7 patients suggests that taking coenzyme Q10 (Vitaline) 120-240 mg orally daily with the goal of raising blood levels above 2 mcg/mL, might improve symptoms of hypertrophic cardiomyopathy, including dyspnea and fatigue, and decrease cardiac wall thickness, when compared to baseline (11031). The validity of these findings is limited by the small size of the study and the lack of a comparator group.
• Infertility. It is unclear if oral coenzyme Q10 helps women undergoing assisted reproductive technology (ART) treatment. Details: Meta-analyses of several lower- to moderate-quality clinical studies in women with infertility undergoing ART treatment, such as in-vitro fertilization, show that pretreatment with coenzyme Q10 increases the odds of clinical pregnancy by approximately 2-fold, but it does not affect the rate of miscarriages or live births when compared with placebo, control, or no treatment (103780,115945). The validity of this data is limited by high-risk bias in analyzed studies.
• Kidney failure. Oral coenzyme Q10 has been reported to improve renal function in people with kidney failure, but not in those with less severe kidney disease. Details: Preliminary clinical research in patients with kidney failure shows that taking coenzyme Q10 180 mg orally daily for 28 days improves blood urea nitrogen, serum creatinine, and creatinine clearance when compared with placebo (44347). However, other clinical research in patients with less severe kidney disease shows that taking coenzyme Q10 200 mg daily for 8 weeks does not significantly improve kidney function parameters, including urinary albumin, total protein, or glomerular filtration rate, when compared with placebo (44128).
• Lichen planus. It is unclear if topical coenzyme Q10 is beneficial for oral lichen planus. Oral coenzyme Q10 has not been studied for this condition. Details: A small clinical study in patients with oral lichen planus conducted in Egypt shows that applying topical coenzyme Q10 (ubiquinol) 120 mg as a mucoadhesive tablet 3 times daily for 4 weeks does not improve pain scores or lesion size when compared with topical corticosteroid paste (111617).
• Male Infertility. Oral coenzyme Q10 may improve some measures of sperm function in males with infertility, but there is no convincing evidence that it can increase pregnancy rates. Details: One small clinical study in males with idiopathic asthenozoospermia shows that coenzyme Q10 200 mg orally daily for 6 months improves sperm motility when compared with baseline (12169). The validity of this finding is limited by the lack of a comparator group. Coenzyme Q10 has also been studied in males with idiopathic oligoasthenoteratozoospermia (iOAT), but results are conflicting. Studies have used coenzyme Q10 or its reduced form, ubiquinol, in doses of 200-300 mg orally daily for 26 weeks. Sperm density and motility are increased when compared with placebo, but pregnancy rates do not seem to improve (17413,89422). Three studies have used coenzyme Q10 200-400 mg orally daily for 12-26 weeks, with two reporting increased sperm concentration and motility when compared to baseline, but the other finding no improvements when compared with placebo (44190,102008,107444). Coenzyme Q10 has also been investigated in combination with other ingredients with varying results. Three small clinical studies in adults show that taking a specific combination product providing coenzyme Q10 20 mg twice daily for 6 months, along with acetyl-L-carnitine, L-carnitine, selenium, zinc, vitamin C, folic acid, vitamin B12, and citric acid (Proxeed Plus) improves measures of sperm quality such as sperm count, sperm concentration, total motility, and progressive motility when compared to baseline; however, the effect on sperm volume and morphology is unclear. Most research has been conducted in patients with oligoasthenozoospermia, although some benefit has also been shown in patients with varicocele-related infertility, especially those with more severe varicocele (102017,107395,111296). The validity of these findings is limited by the lack of comparator group. Another clinical trial in adults shows that taking coenzyme Q10 10 mg and vitamin E 100 mg three times daily for 3 months improves progressive sperm motility and morphology when compared to baseline but not when compared with L-carnitine(109390). It is unclear if these effects are due to coenzyme Q10, other ingredients, or the combination. Additionally, a single-center, open-label clinical study in adults with iOAT shows that taking coenzyme Q10 (CoQ-10, Natrol) 400 mg daily with letrozole for 3 months increases total sperm count, sperm concentration, and morphology but does not increase sperm motility when compared with letrozole alone (115947).
• Maternally inherited diabetes mellitus and deafness (MIDD). It is unclear if oral coenzyme Q10 is beneficial for MIDD. Details: One small clinical study shows that taking coenzyme Q10 150 mg orally daily for 3 years might prevent progressive insulin secretory defect, exercise intolerance, and hearing loss when compared with baseline in people with this rare form of diabetes (2125).
• Metabolic syndrome. It is unclear if oral coenzyme Q10 is beneficial in patients with metabolic syndrome. Details: A small clinical study in patients with metabolic syndrome receiving healthy dietary recommendations shows that taking coenzyme Q10 60 mg daily for 12 weeks does not have beneficial effects on blood glucose, cholesterol, waist circumference, or blood pressure when compared with placebo (109284).
• Mitochondrial myopathies. It is unclear if oral coenzyme Q10 is beneficial in patients with mitochondrial myopathies. Details: Very small clinical trials show that taking coenzyme Q10 improves certain mitochondrial myopathies; however, not all research agrees. A specific coenzyme Q10 formulation (UbiQGel, Tishcon Corporation) has been evaluated for mitochondrial myopathies, including MELAS (mitochondrial encephalopathy with lactic acidosis and stroke-like episodes) syndrome, Kearns-Sayre syndrome, and MERRF (myoclonus epilepsy with ragged red fibers). Typical doses are 150-160 mg, or 2 mg/kg, daily, gradually increasing to 3000 mg daily in some cases. The onset of action is slow, with maximal effects around 6 months (8159,8162,8163,8912,11050,44240,97905).
• Myocarditis. It is unclear if oral coenzyme Q10 is beneficial in patients with acute viral myocarditis. Details: A small observational study in Chinese patients with acute viral myocarditis has found that taking coenzyme Q10 10 mg and trimetazidine 20 mg three times daily for 2 weeks, along with standard care, is associated with higher rates of resolution and improved quality of life when compared with coenzyme Q10 plus standard care alone (107443). While coenzyme Q10 alone appeared to improve symptoms and markers of cardiac function when compared to baseline in some patients, the validity of these findings is limited by a lack of placebo control.
• Nonalcoholic fatty liver disease (NAFLD). Coenzyme Q10 may reduce liver enzymes and the severity of NAFLD. Details: Preliminary clinical research in adults with NAFLD shows that taking coenzyme Q10 100 mg orally daily for 12 weeks reduces the clinical grade of NAFLD and decreases plasma levels of liver enzymes when compared with placebo (97907).
• Obesity. Oral coenzyme Q10 does not seem to improve weight loss in adults. Details: A meta-analysis of small, highly heterogeneous clinical trials shows that taking coenzyme Q10 100-300 mg daily for up to 24 weeks does not reduce weight or body mass index when compared with placebo. However, the included studies were not designed to assess for weight loss and involved patients with type 2 diabetes, metabolic syndrome, kidney disease, liver disease, rheumatoid arthritis, and other conditions (105067).
• Periodontitis. Data on the effects of oral or topical coenzyme Q10 are conflicting. It is unclear if coenzyme Q10 is beneficial for periodontitis. Details: Some very small, low-quality studies suggest that taking coenzyme Q10 orally, 50 mg daily for 3 weeks, might be beneficial for periodontitis (8917,8918). Preliminary research with topical coenzyme Q10 suggests it is ineffective (2107,2108). However, a meta-analysis of 11 clinical trials evaluating coenzyme Q10 topical gel shows reductions in plaque index, bleeding index, pocket index, clinical attachment level, and gingival index when compared with placebo gel or scaling and root planing alone. The greatest effects are seen when coenzyme Q10 gel is applied directly into the periodontal pocket daily for at least six weeks in combination with scaling and root planing (108958). The validity of these findings is limited by a high risk of bias and the overall low quality of the included studies. Coenzyme Q10 has also been studied in combination with other ingredients for periodontitis. A small clinical study in patients with moderate or advanced periodontitis shows that taking a supplement containing 30 mg of coenzyme Q10 in addition to alpha-lipoic acid, cranberry extract, grapeseed extract, selenium, vitamin C, vitamin E, and zinc twice daily for 8 weeks in addition to standard nonsurgical therapy does not improve periodontal indices including bleeding on probing, gingival recession, plaque index, or inflammation, among others, when compared with placebo (111708).
• Physical performance. It is unclear if oral coenzyme Q10 improves physical performance in older adults with chronic kidney disease (CKD). Details: A small clinical study in mostly older adults with CKD shows that taking coenzyme Q10 1200 mg daily for 6 weeks does not improve measures of physical exercise endurance including aerobic capacity, total work, and work efficiency when compared with placebo (111558). The validity of these effects is limited by the small sample size and short study duration.
• Polycystic ovary syndrome (PCOS). Most clinical studies suggest that oral coenzyme Q10 modestly improves symptoms in patients with PCOS. Details: A meta-analysis of clinical trials in patients with PCOS shows that taking coenzyme Q10 modestly improves measures of glycemic response, as well as plasma lipids and some sex hormones, when compared with placebo (109384). However, any changes are small and the clinical relevance is unclear. Also, although nine studies were included in the review, the number of studies included for each endpoint was much lower. Most clinical studies included in the analysis used 100-200 mg daily for 8-12 weeks (107446,109384). An additional small clinical study also shows that taking coenzyme Q10 (Nature Made) 100 mg orally daily for 12 weeks reduces fasting plasma glucose, insulin, and total cholesterol and improves insulin sensitivity when compared with placebo. This study also found that taking coenzyme Q10 reduces alopecia by about 33% and acne by 48% when compared with placebo (97914). Another small clinical study shows that taking coenzyme Q10 100 mg daily for 12 weeks reduces depression, anxiety, and hirsutism when compared with placebo (107446).
• Prader-Willi syndrome (PWS). It is unclear if oral coenzyme Q10 is beneficial in patients with PWS. Details: Preliminary clinical research in children with Prader-Willi syndrome shows that taking coenzyme Q10 2.5 mg/kg orally daily for one year improves psychomotor development similarly to growth hormone therapy, although this might reflect natural changes in the condition occurring over time (44005).
• Pre-eclampsia. Taking coenzyme Q10 orally seems to reduce the rate of pre-eclampsia in women at risk for the condition. Details: Clinical research shows that taking coenzyme Q10 (Q-absorb, Jarrow Formulas) 100 mg orally twice daily during pregnancy, starting at 20 weeks gestation and continuing until term, reduces the rate of pre-eclampsia by about 44% when compared with placebo in women at risk for developing this condition (17201).
• Schizophrenia. It is unclear if oral coenzyme Q10 improves symptoms in patients with schizophrenia or schizoaffective disorder. Details: A small clinical study in patients with schizophrenia or schizoaffective disorder shows that taking coenzyme Q10 300 mg daily for 6 months does not improve attention, working memory, negative symptoms, mood disorders, or quality of life when compared with placebo (105069). This finding is limited by insufficient power and poor protocol adherence, with only 61% of the participants taking at least 90% of the study treatment.
• Sepsis. There is no strong evidence that coenzyme Q10 is helpful in the management of sepsis or septic shock. Details: Patients with septic shock have been shown to have low levels of coenzyme Q10, but the effects of supplementation are unclear. Some preliminary clinical research shows that taking coenzyme Q10 100 mg orally twice daily for 7 days reduces the risk of in-hospital mortality by 69% and improves markers of inflammation, but does not reduce length of ICU stay, when compared with conventional treatment alone (102548). However, other preliminary research shows that taking coenzyme Q10 as ubiquinol 200 mg twice daily for 7 days has no effect on inflammatory or vascular endothelial biomarkers, mortality, or length of stay when compared with placebo (96540). Both studies were small and likely underpowered to detect a meaningful change in clinical outcomes.
• Statin-induced myalgia. There is conflicting evidence regarding the effects of oral coenzyme Q10 on statin-associated muscular adverse effects, such as myalgia. Details: Some clinical research shows that taking coenzyme Q10 (Q-Sorb softgel, Nature's Bounty) 100 mg orally daily for 30 days reduces pain intensity when compared with baseline or vitamin E control in patients with statin-induced myalgia (16008,44345). Other clinical research shows that taking coenzyme Q10 (MGC Company) 50 mg orally twice daily for 30 days reduces muscle pain and pain interference with daily activities by 30% to 40% when compared with placebo (95604). One small study in adults with statin-induced myalgia shows that taking liquid coenzyme Q10 (Q-Factor, Giellepi S.p.A) 100 mg orally daily for 3 months modestly reduces pain scores, but not plasma creatine kinase (CK) levels, when compared with placebo (102007). Other clinical research shows that taking coenzyme Q10 (Bio-Quinon, Pharma Nord) 100 mg twice daily, with or without selenium, for 3 months, reduces muscle pain and weakness, cramps, and tiredness when compared with placebo (92909). However, not all studies have shown benefit. Meta-analyses of several small randomized controlled trials show that taking coenzyme Q10 100-600 mg daily for 1-3 months does not improve muscle pain, statin tolerability, or plasma CK activity in patients with statin-induced myalgia when compared with placebo (95602,103781,106050). However, the validity of these results is limited by small population size and high heterogeneity. Other clinical research shows that taking coenzyme Q10 60 mg twice daily for 3 months does not improve muscle pain when compared with placebo (44218). Also, taking coenzyme Q10 (Q-Gel, Tishcon Corporation) 200 mg daily for 12 weeks does not affect myalgia scores when compared with placebo in patients taking simvastatin (44346). Additionally, taking high doses of coenzyme Q10 600 mg daily for 8 weeks does not affect the incidence, severity, or time to onset of statin-induced myalgia when compared with placebo in patients taking simvastatin (95603). Reasons for these conflicting findings are not entirely clear. The inconsistent results do not appear to be related to the dose of coenzyme Q10 or plasma CK levels. About 50% of patients who experience statin-induced myalgia will tolerate a statin re-challenge with a lower or equivalent dose of the same or alternative statin after a statin-free interval, which is a higher response rate than seen in currently available studies with the use of coenzyme Q10. Taking coenzyme Q10 for 30 days may be a reasonable option if other attempts to improve tolerance have failed. If a significant improvement in pain related to statin use is not seen after 30 days of taking coenzyme Q10, it is unlikely to be beneficial (96548).
• Statin-induced myopathy. There is conflicting evidence regarding the effects of coenzyme Q10 on statin-associated muscular adverse effects, including myopathy. Details: Clinical research shows that taking coenzyme Q10 (Bio-Quinon, Pharma Nord) 100 mg orally twice daily, with or without selenium, for 3 months, reduces muscle weakness and pain, cramps, and tiredness when compared with placebo in patients with statin-induced myopathy due to atorvastatin, fluvastatin, rosuvastatin, or simvastatin (92909). Preliminary clinical research also shows that taking coenzyme Q10 60 mg orally four times daily decreases the rate of dose-limiting statin-induced myopathy in patients taking high-dose lovastatin as an investigational treatment for cancer (11899,11900). However, when coenzyme Q10 (Myoquinon, Pharma Nord,) 400 mg orally daily is used in combination with selenium for 12 weeks, it does not affect atorvastatin-induced myopathy when compared with placebo (92908).
• Toxin-induced liver damage. Oral coenzyme Q10 has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients being treated with anti-tuberculosis drugs shows that taking coenzyme Q10 200 mg, acetyl-L-carnitine 250 mg, and alpha-lipoic acid 250 mg twice daily for 2 weeks reduces the risk of drug-induced liver injury by 73% when compared with placebo (107445). It is unclear if these findings are due to coenzyme Q10, other ingredients, or the combination.
• Ulcerative colitis. It is unclear if oral coenzyme Q10 is beneficial in patients with ulcerative colitis. Details: Preliminary clinical research in adults with ulcerative colitis shows that taking oral coenzyme Q10 (Nutri Q10, Nutri Century Company) 100 mg twice daily for 8 weeks modestly improves ulcerative colitis disease activity and quality of life scores when compared with placebo. Taking coenzyme Q10 also reduces systolic and diastolic blood pressure by 4 mmHg and 2 mmHg, respectively, when compared with placebo (106049). The clinical relevance of these changes is unclear.
• Wound healing. It is unclear if topical application of coenzyme Q10 is beneficial for wound healing. Details: A small clinical study in adults undergoing oral surgery for gingival recession shows that application of coenzyme Q10 spray (45 mg/mL) to oral wounds 3 times daily for 3 weeks does not promote wound healing or improve patient-reported pain when compared with placebo (115948).
• Wrinkled skin. It is unclear if topical application of coenzyme Q10 cream can reduce wrinkles. Details: A small clinical study shows that applying a coenzyme Q10 1% cream to the skin twice daily for 5 months reduces objective wrinkle scores when compared to baseline (44082). The validity of this finding is limited by the lack of a comparator group. More evidence is needed to rate coenzyme Q10 for these uses.

(Read more about COENZYME Q10)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Angina. Although there has been interest in using oral coleus for angina, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Asthma. It is unclear if inhaled forskolin, a constituent of coleus, is beneficial in patients with asthma. Details: A preliminary clinical trial in patients with asthma shows that a single-dose inhalation of the powdered coleus constituent, forskolin, 10 mg, from a Spinhaler inhaler increases forced expiratory volume in one second (FEV1) when compared to baseline (7281,44432). Another, low-quality, trial in patients with asthma found that using a specific forskolin product (Pro-longevity Forskolin, Life Extension Foundation Buyers Club, Fort Lauderdale, Florida, USA) providing forskolin 10 mg per day orally for 6 months did not improve lung function, but resulted in fewer asthma attacks when compared to two inhalations of sodium cromoglycate three times daily for 6 months (91889). However, another preliminary trial in adults and children with mild asthma shows that taking oral forskolin 10 mg taken daily for 2 months, neither reduced asthma attacks nor improved lung function when compared with beclomethasone inhalations or when compared to baseline (91883).
• Atopic dermatitis (eczema). Although there has been interest in using oral coleus for atopic dermatitis, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Cancer. Although there has been interest in using oral coleus for cancer, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Congestive heart failure (CHF). Although there has been interest in using intravenous forskolin, a constituent of coleus, for CHF, there is insufficient reliable information about the clinical effects of forskolin or coleus for this purpose.
• Dilated cardiomyopathy. It is unclear if intravenous forskolin, a constituent of coleus, is beneficial in patients with dilated cardiomyopathy. Details: Preliminary clinical research in patients with dilated cardiomyopathy shows that using intravenous coleus 0.5 mcg/kg/minute, titrated at 15 minute intervals to 3 mg/kg/minute, increases cardiac output and pulmonary vascular pressure when compared to baseline (7278). The validity of this study is limited by the lack of a comparator group.
• Dry eye. Oral coleus has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with dry eyes shows that taking a specific combination supplement (Kronek, SOOFT Italia, Montegiorgio, Italy) containing an extract of Coleus forskolii 150 mg (10% forskolin), rutin 200 mg, thiamine 0.7 mg, and riboflavin 0.8 mg, 2 capsules by mouth daily for 30 days moderately decreases dry eye symptoms when compared with placebo (91888). It is unclear if this benefit is due to coleus, other ingredients, or the combination.
• Dysmenorrhea. Although there has been interest in using oral coleus for dysmenorrhea, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Erectile dysfunction (ED). It is unclear if intracavernosal forskolin, a constituent of coleus, is beneficial in patients with ED. Details: Preliminary clinical evidence in males with ED treated with intracavernosal injections of phentolamine, papaverine, and prostaglandin E shows that intracavernosal forskolin, a constituent of coleus, 1 mg once daily improves penile rigidity scores and average erection duration when compared to no additional intervention (44441).
• Glaucoma. Oral coleus has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking two tablets of a specific combination supplement (Kronek Sooft Italia SpA, Montegiorgio, Italy) containing forskolin 15 mg, rutin 200 mg, vitamin B1 1.5 mg, and vitamin B2 1.5 mg for 7 or 30 days prevents increases in intraocular pressure and decreases intraocular pressure by 10% when compared with placebo in glaucoma patients (91887,91890). Preliminary clinical research on another specific combination supplement (Gangliolife, SOOFT Italia), two tablets taken twice daily for 1 year in addition to standard topical therapy results in a decrease in intraocular pressure compared to standard therapy alone in patients with primary open angle glaucoma. One tablet of the supplement contains coleus extract 150 mg (standardized to 10% forskolin), homotaurine 100 mg, L- carnosine 50 mg, vitamin B1 1.1 mg, vitamin B2 1.4 mg, vitamin B6 1.4 mg, folic acid 0.2 mg, and magnesium 150 mg (91886).
• Hypertension. It is unclear if oral coleus is beneficial in patients with hypertension. Details: Preliminary clinical research shows that taking coleus root tuber 1 gram or coleus whole root 1.4 grams orally three times daily after food for 2 months modestly decreases blood pressure compared to baseline in elderly patients with hypertension (91884). The validity of this study is limited by the lack of a comparator group.
• Insomnia. Although there has been interest in using oral coleus for insomnia, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Irritable bowel syndrome (IBS). Although there has been interest in using oral coleus for irritable bowel syndrome, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Obesity. It is unclear if oral coleus is beneficial in patients with obesity. Details: Preliminary clinical research in overweight and obese males shows that taking a specific coleus supplement (Forslean, Sabina Corp., Piscataway, NJ) containing a 10% forskolin extract 250 mg twice daily for 12 weeks does not decrease body weight when compared with placebo. However, taking the supplement lowered body fat by 4% compared with 1% in placebo (91882). Another small clinical trial in overweight and obese patients following a calorie-restricted diet shows that taking a coleus extract capsule 250 mg twice daily before meals for 12 weeks does not reduce body weight when compared with placebo (91885).
• Psoriasis. Although there has been interest in using oral coleus for psoriasis, there is insufficient reliable information about the clinical effects of coleus for this purpose.
• Urinary tract infections (UTIs). Although there has been interest in using oral coleus for UTIs, there is insufficient reliable information about the clinical effects of coleus for this purpose. More evidence is needed to rate coleus for these uses.

(Read more about COLEUS)

There is insufficient reliable information available about the effectiveness of goldthread.

(Read more about GOLDTHREAD)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Anxiety. Oral guarana has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking two tablets of a specific product (Euphytose) containing hawthorn, black horehound, passionflower, valerian, cola nut, and guarana three times daily for 28 days can reduce the severity of anxiety in a greater percentage of patients with adjustment disorder with anxious mood compared to placebo (6250). However, because guarana was included in the supplement as a mild stimulant, it is unclear if this component contributed to the antianxiety effect of the product.
• Athletic performance. Oral guarana has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking a single dose of a specific product (Berocca Boost, Bayer) containing guarana 222.2 mg (standardized to 40 mg caffeine), B vitamins, vitamin C, and minerals slightly improves exercise tolerance in trained individuals by approximately 2% when compared with placebo (91491). A small crossover study in young adult recreational handball players shows that taking a specific multi-ingredient supplement product (Olimp, Poland) containing guarana, caffeine, and other ingredients (total caffeine content 300 mg) prior to exercise slightly improves the time to complete agility testing but does not increase jump height when compared with placebo. However, taking a supplement containing only guarana and caffeine (total caffeine content 300 mg) does not improve agility or jump height (111577). It is unclear if the effects in these studies are due to guarana, other ingredients, or the combination.
• Cancer-related anorexia. It is unclear if oral guarana is beneficial for anorexia in patients with cancer. Details: A preliminary clinical study shows that taking guarana extract might improve appetite and reduce weight loss in some patients with cancer-related anorexia. Taking guarana extract (Pharmanostra) 50 mg twice daily for 4 weeks stabilized or increased weight in 55% of patients and stabilized or improved appetite in 89% of patients. However, only two patients achieved a weight gain of at least 5%, which was the minimum weight gain considered to be a positive response (91487).
• Cancer-related fatigue. It is unclear if oral guarana is beneficial for fatigue in patients with cancer. Details: Meta-analyses of small clinical studies in patients with solid tumors or breast cancer who are receiving chemotherapy or radiation therapy show that taking guarana 75-100 mg daily for 2-12 weeks does not improve cancer-related fatigue when compared with placebo (108016,111576). Additionally, a systematic review of clinical studies in patients with a variety of solid tumor types found no difference in cancer-related fatigue following at least 5 weeks of guarana consumption (108016). Most studies included in the meta-analysis and systematic review were low-quality, and all studies were conducted in Brazil. Higher quality studies in other geographic locations are needed to confirm these findings.
• Chemotherapy-related fatigue. It is unclear if oral guarana is beneficial for fatigue in patients receiving chemotherapy. Details: In patients with breast cancer, clinical research shows taking guarana extract 50 mg twice daily for 21 days improves fatigue in 52% to 66% of patients, compared with only 10% to 13% in the placebo group (91482). Other preliminary clinical research shows that taking guarana extract 37.5 mg twice daily for 3 weeks improves or stabilizes fatigue in 90% of patients with chemotherapy-related fatigue when compared with baseline. However, when compared with placebo for an additional 3 weeks, guarana does not affect fatigue (91483). Other clinical research shows that taking a dried, purified extract of guarana (PC-18) in doses of 7.5, 12.5, or 37.5 mg twice daily for 21 days improves fatigue in patients with breast cancer when compared with baseline, but not when compared with placebo. It is possible that the magnesium silicate used as a filler in both active and placebo treatments in this study contributed a fatigue-reducing effect (99049).
• Chronic fatigue syndrome (CFS). Although there has been interest in using oral guarana for CFS, there is insufficient reliable information about the clinical effects of guarana for this condition.
• Cognitive function. It is unclear if oral guarana is beneficial for improving cognitive function. Details: In healthy individuals, some clinical research shows that taking a single dose of guarana dry extract 37.5-75 mg, containing 11% to 12% caffeine, improves the speed of cognitive task performance and memory for up to 6 hours, but does not improve reaction time or speed and accuracy of memory, when compared with placebo. Higher doses of guarana 150-300 mg do not appear to be effective (54374,91484). However, a small clinical study in young adult cyclists shows that taking guarana powder 125 mg/kg 30 minutes prior to cognitive testing improves reaction time and alertness scores when compared with placebo, but not when compared with caffeine (111361). Other clinical research shows that taking guarana powder 500 mg, containing 2.1% to 2.5% caffeine, twice daily for 3-150 days does not improve cognitive function when compared with placebo in adults or elderly individuals (54402,54414). Some research has evaluated guarana in combination with other ingredients. Preliminary clinical studies show that taking a specific product containing guarana 222 mg, B vitamins, vitamin C, and minerals (Berocca Boost, Bayer) can improve the speed and accuracy of visual information processing, working memory, and attention, as well as decrease mental fatigue, when compared to placebo (91485,91489,91491). Another specific combination product containing guarana 300 mg and other ingredients (Isoxan Actiflash, Menarini, NHS) improves reaction time by almost 600 msec for up to 90 minutes when compared with placebo or caffeine alone (91488). Conversely, a small clinical study in experienced young-adult video gamers shows that taking guarana 500 mg in combination with microalgae extract 440-880 mg daily for 30 days does not improve most measures of accuracy, reaction time, or gaming performance when compared to baseline (111360). A meta-analysis of 8 small clinical studies in healthy adults, that includes many of these studies, shows that taking a single dose of guarana 37.5-500 mg (median dose 222 mg; caffeine content 4-100 mg), alone or with other ingredients (i.e., B vitamins, vitamin C), within 360 minutes before a cognitive task does not improve overall cognitive performance or accuracy, but modestly improves reaction time when compared with placebo. In addition, cognitive performance was not related to guarana dose (111359). The validity of this analysis is limited by the heterogeneity of the included studies which utilized widely varying doses and various cognitive tests.
• Dysmenorrhea. Although there has been interest in using oral guarana for dysmenorrhea, there is insufficient reliable information about the clinical effects of guarana for this condition.
• Dyspepsia. Although there has been interest in using oral guarana for dyspepsia, there is insufficient reliable information about the clinical effects of guarana for this purpose.
• Erectile dysfunction (ED). Oral guarana has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: In middle-aged patients with ED, preliminary clinical research shows that taking two capsules of a specific combination product (Revactin, MD Concepts LLC) containing guarana 125 mg, muira puama 125 mg, ginger root 125 mg, and L-citrulline 400 mg twice daily for 3 months improves scores related to erectile function and intercourse satisfaction, but not sexual desire or orgasmic function, when compared to baseline (103224). The validity of this study is limited by the lack of a placebo control, the use of per-protocol analysis, and a high dropout rate. In fact, 44% of patients withdrew in order to resume use of phosphodiesterase type 5 (PDE5) inhibitors. Further, it is unclear if these effects are due to guarana, other ingredients, or the combination.
• Fatigue. Although there has been interest in using oral guarana for fatigue, there is insufficient reliable information about the clinical effects of guarana for this purpose.
• Headache. Although there has been interest in using oral guarana for headache, there is insufficient reliable information about the clinical effects of guarana for this purpose.
• Obesity. Oral guarana has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One very small exploratory clinical study in overweight females shows that taking guarana 855 mg, yerba mate 1008 mg, and damiana 325 mg in divided doses daily for up to 45 days delays gastric emptying, increases satiety, and modestly improves weight loss when compared to baseline (11866). The validity of these findings is limited by the small study size and lack of a comparator group.
• Psychological well-being. It is unclear if oral guarana is beneficial for improving feelings of well-being. Details: Preliminary clinical research shows that taking guarana 1080 mg daily after breakfast for 5 days does not improve feelings of well-being or mood in healthy individuals (91490).
• Radiation-induced fatigue. It is unclear if oral guarana is beneficial for improving fatigue related to radiation therapy. Details: A small clinical trial shows that taking guarana 75 mg daily does not improve symptoms of depression or fatigue when compared with placebo in patients with breast cancer undergoing radiation therapy treatments (91481).

(Read more about GUARANA)

POSSIBLY EFFECTIVE

• Back pain. Oral willow bark extract has been evaluated for the treatment of back pain, with promising results. Details: Clinical research in patients with chronic low back pain shows that taking a standardized willow bark extract providing salicin 120 mg or 240 mg daily for 4 weeks reduces lower back pain and decreases the need for rescue analgesia when compared with placebo. Salicin 240 mg appears to be more effective than salicin 120 mg, and significant pain relief may be observed after 1 week of high-dose use (6456). Additional research suggests that taking willow bark extract providing salicin 240 mg daily for 4 weeks is as effective as rofecoxib (Vioxx) for lower back pain (12804).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Ankylosing spondylitis. Although there has been interest in using oral willow bark for pain associated with ankylosing spondylitis, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Common cold. Although there has been interest in using oral willow bark for common cold symptoms, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Dysmenorrhea. Although there has been interest in using oral willow bark for dysmenorrhea, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Gout. Although there has been interest in using oral willow bark for gout, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Headache. Although there has been interest in using oral willow bark for headache, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Influenza. Although there has been interest in using oral willow bark for pain and fever associated with influenza, including swine flu, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Joint pain. Oral willow bark has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in patients with joint pain shows that taking capsules of a specific combination product (Instaflex Joint Support, Direct Digital) containing glucosamine sulfate 500 mg, methylsufonlylmethane 167 mg, white willow bark extract 83 mg, ginger root concentrate 17 mg, boswellia extract 42 mg, turmeric root extract 17 mg, cayenne 40 m H.U. 17 mg, and hyaluronic acid 1.3 mg three times daily for 8 weeks reduces joint pain severity by 37% compared to only 16% with placebo. However, the specific combination product does not appear to significantly improve joint stiffness or function when compared with placebo (89560). It is unclear if these findings are due to willow bark, other ingredients, or the combination.
• Myalgia. Although there has been interest in using oral willow bark for myalgia, there is insufficient reliable information about the clinical effects of willow bark for this purpose.
• Obesity. Oral willow bark has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research suggests that willow bark in combination with ephedra and cola nut might cause modest weight loss in overweight and obese people. Willow bark 600 mg daily (containing 90 mg salicin) in divided doses given for 3 months in combination with these central nervous system stimulants might cause a 2 kg reduction in weight (12811). However, this combination may not be appropriate due to safety concerns associated with ephedra. Ephedra is banned in the US due to severe adverse effects (10055).
• Osteoarthritis. Small clinical studies suggest that oral willow bark extract may improve symptoms of osteoarthritis, although some conflicting evidence exists. Details: Some preliminary clinical research in patients with osteoarthritis shows that taking willow bark extract standardized to contain 240 mg of salicin daily for 2 weeks produces moderate analgesic activity when compared with placebo (12474,86490). Additional research shows that taking a specific willow bark extract (Optovit actiFLEX, Hermes Arzneimittel GmbH) standardized to contain salicin 120-240 mg daily for 6 weeks improves swelling, tenderness, and physical function similarly to conventional non-steroidal anti-inflammatory drugs (NSAIDs) (91406). However, other research shows that taking willow bark extract standardized to 240 mg of salicin daily for 6 weeks does not improve pain, stiffness, or physical function when compared with placebo (12475).
• Rheumatoid arthritis (RA). It is unclear if oral willow bark is beneficial in patients with RA. Details: Clinical research in a small number of patients with RA shows that willow bark extract standardized to 240 mg of salicin daily for 6 weeks does not improve pain when compared with placebo (12475). However, it is possible this study was underpowered to detect a significant difference in pain in these patients. More evidence is needed to rate willow bark for these uses.

(Read more about WILLOW BARK)

POSSIBLY SAFE ...when used orally and appropriately. Berberine has been used safely in doses up to 1.5 grams daily for 6 months (262,13520,20579) (34317,34228,34247,34253,34262,34263,34265,34267,34277,34282), (34283,34286,34287,34289,34293,34301,34305,34306,34319,34325)(99920,99921,103194) or up to 1 gram daily for 24 months (99921,103197). ...when used topically. Berberine ointment has been applied with apparent safety for up to 20 days (13526).

CHILDREN: LIKELY UNSAFE
when used orally in newborns. Berberine can cause kernicterus, particularly in preterm neonates with hyperbilirubinemia (2589). It is unclear if berberine is safe in older children.

PREGNANCY: LIKELY UNSAFE
when used orally. Berberine is thought to cross the placenta and may cause harm to the fetus. Kernicterus has developed in newborn infants exposed to berberine (2589). Also, berberine may stimulate uterine contractions (91951).

LACTATION: LIKELY UNSAFE
when used orally. Berberine can be transferred to the infant through breast milk (2589).

(Read more about BERBERINE)

LIKELY SAFE ...when used orally and appropriately. Coenzyme Q10 has been used safely in studies lasting up to 5 years (2134,6037,6038,6407,8163,8938,8939,8940,15395,17413,17716,96538)(109391). ...when used topically on the gums (2107,2108,8916,8917,8918).

CHILDREN: POSSIBLY SAFE
when used orally and appropriately. Coenzyme Q10 in doses of 1-10 mg/kg/day has been used safely for up to 9 months under medical supervision (12199,13223,15256,44005,107449).

PREGNANCY: POSSIBLY SAFE
when used orally and appropriately. Coenzyme Q10 100 mg twice daily has been used with apparent safety during pregnancy, starting at 20 weeks gestation until term (17201).

LACTATION:
Insufficient reliable information available; avoid using.

(Read more about COENZYME Q10)

POSSIBLY SAFE ...when used orally and appropriately, short-term. Coleus extract 500 mg daily has been used for up to 3 months without significant adverse effects (91885,100851). ...when used intravenously and appropriately, short-term. Intravenous forskolin, a constituent of coleus, seems to be safe when given at an appropriate rate of 0.5 mcg/kg/minute and increased at 15 minute intervals to 1.0, 2.0, and 3.0 mcg/kg/minute up to 1 hour (7278,7279). ...when used by inhalation and appropriately. Single-dose inhalation of forskolin powder 10 mg from a Spinhaler inhalator seems to be safe and well-tolerated (7281). ...when used ophthalmologically and appropriately. Coleus suspension eye drops (1%) have been safely used in clinical studies (7282,7283,7284,7402,7403,7405).

POSSIBLY UNSAFE ...when used orally in higher doses. Although coleus extracts have been used with apparent safety in doses up to 1.4 grams daily for 2 months (91884), taking coleus extract in doses exceeding 500 mg daily has been associated with an increased incidence of adverse effects, which are primarily gastrointestinal (100851).

PREGNANCY: POSSIBLY UNSAFE
when used orally. Evidence from animal research suggests that high doses of coleus can inhibit embryo implantation and/or delay fetal development (25174); avoid using.

LACTATION:
Insufficient reliable information available; avoid using.

(Read more about COLEUS)

There is insufficient reliable information available about the safety of goldthread when used in adults in medicinal amounts.

CHILDREN: LIKELY UNSAFE
when used orally in newborns. The berberine constituent of goldthread can cause kernicterus in newborns, particularly preterm neonates with hyperbilirubinemia (2589).

PREGNANCY: LIKELY UNSAFE
when used orally. Berberine is thought to cross the placenta and may cause harm to the fetus. Kernicterus has developed in newborn infants exposed to berberine (2589). Preliminary evidence suggests that maternal intake of goldthread during the first trimester increases the risk of congenital malformations of the central nervous system (15129).

LACTATION: LIKELY UNSAFE
when used orally. Berberine and other harmful constituents can be transferred to the infant through breast milk (2589).

(Read more about GOLDTHREAD)

LIKELY SAFE ...when consumed in amounts typically found in foods. Guarana has Generally Recognized as Safe (GRAS) status for use in foods in the US (4912).

POSSIBLY SAFE ...when used orally and appropriately, short-term (12). Guarana contains caffeine. According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, doses of caffeine up to 400 mg daily are not associated with significant adverse cardiovascular, bone, behavioral, or reproductive effects in healthy adults (11733,98806). The US Dietary Guidelines Advisory Committee states that there is strong and consistent evidence that consumption of caffeine 400 mg daily is not associated with increased risk of major chronic diseases, such as cardiovascular disease or cancer, in healthy adults (98806).

POSSIBLY UNSAFE ...when used orally long-term or in high doses. Guarana contains a significant amount of caffeine. Chronic use, especially in large amounts, can produce tolerance, habituation, psychological dependence, and other significant adverse effects. Acute use of high doses, typically above 400 mg per day, has been associated with significant adverse effects such as tachyarrhythmias and sleep disturbances (11832,95503,98806). These effects would not be expected to occur with the consumption of decaffeinated guarana.

LIKELY UNSAFE ...when used orally in very high doses. The fatal acute oral dose of caffeine is estimated to be 10-14 grams (150-200 mg per kilogram). Serious toxicity can occur at lower doses depending on variables in caffeine sensitivity such as smoking, age, or prior caffeine use (11832,54425).

PREGNANCY: POSSIBLY SAFE
when consumed in amounts commonly found in foods. Due to the caffeine content of guarana, intake should be closely monitored during pregnancy to ensure moderate consumption. Although it is not considered a teratogen, caffeine crosses the placenta and causes dose-dependent increases in fetal blood concentrations (4260). The use of caffeine during pregnancy is controversial; however, moderate consumption has not been associated with clinically important adverse fetal effects (2708,2709,2710,2711,9606,11733,16014,16015,98806). In some studies, consuming amounts over 200 mg daily is associated with a significantly increased risk of miscarriage (16014). This increased risk may be most likely to occur in individuals with genotypes that confer a slow rate of caffeine metabolism (98806). According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, caffeine can be safely consumed in doses up to 300 mg daily without an increased risk of spontaneous abortion, stillbirth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). However, some research has also found that intrauterine exposure to even modest amounts of caffeine, based on maternal blood levels during the first trimester, is associated with a shorter stature in children ages 4-8 years (109846). Advise individuals to keep caffeine consumption below 300 mg daily during pregnancy.

PREGNANCY: POSSIBLY UNSAFE
when used orally in amounts over 300 mg daily. Although it is not considered a teratogen, caffeine crosses the placenta and causes dose-dependent increases in fetal blood concentrations (4260,98806). Consumption of caffeine in amounts over 300 mg daily is associated with a significantly increased risk of miscarriage in some studies (16014,98806). Advise keeping caffeine consumption from all sources below 300 mg daily. High maternal doses of caffeine throughout pregnancy have resulted in symptoms of caffeine withdrawal in newborn infants (9891). High doses of caffeine have also been associated with spontaneous abortion, premature delivery, and low birth weight (2709,2711).

LACTATION: POSSIBLY SAFE
when used orally in amounts commonly found in foods. Due to the caffeine content of guarana, intake should be closely monitored when breast-feeding. Breast milk concentrations of caffeine are thought to be approximately 50% of serum concentrations (9892).

LACTATION: POSSIBLY UNSAFE
when used orally in large amounts. Consumption of guarana might cause irritability and increased bowel activity in nursing infants (6026). Large doses or excessive intake of guarana should be avoided when breast-feeding.

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POSSIBLY SAFE ...when used orally and appropriately, short-term. Willow bark has been used safely for up to 12 weeks (6456,12474,12475,12804,12811,86473,91406).

CHILDREN: POSSIBLY UNSAFE
when used orally for viral infections. Salicylic acid and aspirin are contraindicated in children with viral infections (12801). Although Reye's syndrome has not been reported, the salicin constituent in willow bark is similar to aspirin and might pose the same risk.

PREGNANCY:
Insufficient reliable information available; avoid using.

LACTATION: POSSIBLY UNSAFE
when used orally. Willow bark contains salicylates which are excreted in breast milk and have been linked to adverse effects in breast-fed infants (12802,12803).

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, berberine might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.  Details In vitro and in vivo research suggest that berberine can inhibit platelet aggregation (33660,33694). Theoretically, berberine might have additive effects when used with anticoagulant and antiplatelet drugs and increase the risk of bleeding.

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, berberine may increase the risk of hypoglycemia when taken with antidiabetes drugs.  Details Clinical research shows that berberine may lower blood glucose levels (20579,34247,34265,34282,111363). Theoretically, berberine might have additive effects with antidiabetes drugs and increase the risk of hypoglycemia.

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, berberine might have additive effects with antihypertensive drugs.  Details Animal research suggests that berberine can have hypotensive effects (33692,34308). Also, a clinical study suggests that taking berberine in combination with amlodipine can lower systolic and diastolic blood pressure when compared with amlodipine alone (91956).

CNS DEPRESSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, berberine might increase the sedative effects of CNS depressants.  Details Animal research suggests that berberine may have sedative effects (13519,33650,33664,33692). Theoretically, use of berberine along with CNS depressants might produce additive therapeutic and adverse effects.

CYCLOSPORINE (Neoral, Sandimmune) Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = A Berberine can increase serum levels of cyclosporine.  Details Berberine can reduce metabolism and increase serum levels of cyclosporine. Berberine might inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine (13524,21112,34239).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, berberine might increase serum levels of drugs metabolized by CYP2C9.  Details Preliminary clinical research shows that berberine can inhibit CYP2C9 (34279). Theoretically, taking berberine with drugs metabolized by CYP2C9 might increase drug levels and increase the risk of adverse effects.

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, berberine might increase serum levels of drugs metabolized by CYP2D6.  Details In vitro research and preliminary clinical evidence show that berberine can inhibit CYP2D6 (21117,34279,34297). Theoretically, use of berberine with drugs metabolized by CYP2D6 might increase drug levels and increase the risk of adverse effects.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = A Theoretically, berberine might increase serum levels of drugs metabolized by CYP3A4.  Details In vitro research and preliminary clinical research show that berberine moderately inhibits CYP3A4 (13524,21114,34279,34297). Theoretically, use of berberine with drugs metabolized by CYP3A4 might increase drug levels and increase the risk of adverse effects.

DEXTROMETHORPHAN (Robitussin DM, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, berberine may increase serum levels of dextromethorphan.  Details Preliminary clinical research shows that berberine can inhibit cytochrome P450 2D6 (CYP2D6) activity and reduce the metabolism of dextromethorphan (34279). This may increase the effects and side effects of dextromethorphan.

LOSARTAN (Cozaar) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Berberine might reduce the therapeutic effects of losartan by decreasing its conversion to its active form.  Details Preliminary clinical research suggests that berberine can inhibit cytochrome P450 2C9 (CYP2C9) activity and reduce metabolism of losartan (34279).

METFORMIN (Glucophage) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, berberine might increase the therapeutic and adverse effects of metformin.  Details In vitro and animal studies show that berberine can increase the systemic exposure and half-life of metformin, potentially increasing metformin's effects and side effects. This interaction seems to be most apparent when berberine is administered 2 hours prior to metformin. Taking berberine and metformin at the same time does not appear to increase systemic exposure to metformin (103195).

MIDAZOLAM (Versed) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Berberine can reduce metabolism of midazolam, which might increase the risk of severe adverse effects.  Details Preliminary clinical research shows that berberine can inhibit cytochrome P450 3A4 (CYP3A4) activity and reduce metabolism of midazolam (34279).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Berberine might increase the sedative effect of pentobarbital.  Details Evidence from animal research shows that berberine can prolong pentobarbital-induced sleeping time (13519). Theoretically, combining berberine and pentobarbital might increase the sedative effects of pentobarbital.

TACROLIMUS (Prograf) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Berberine has been associated with increased blood levels of tacrolimus.  Details In a 16-year-old patient with idiopathic nephrotic syndrome who was being treated with tacrolimus 6.5 mg twice daily, intake of berberine 200 mg three times daily increased the blood concentration of tacrolimus from 8 to 22 ng/mL. Following a reduction of the tacrolimus dose to 3 mg daily, blood levels of tacrolimus decreased to 12 ng/mL (91954).

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ALKYLATING AGENTS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Coenzyme Q10 has antioxidant effects. Theoretically, this may reduce the activity of chemotherapy drugs that generate free radicals.  Details Theoretically, antioxidants such as coenzyme Q10 might protect tumor cells from chemotherapeutic agents that work by inducing oxidative stress, such as alkylating agents (e.g., cyclophosphamide) and radiation therapy (5158,5159). The clinical importance of this interaction is unknown.

ANTIHYPERTENSIVE DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.  Details Some clinical research shows that coenzyme Q10 can significantly lower blood pressure (2122,3365,8907,9890,17702,17650,17651,44343,96541), although other studies have shown conflicting results (17651,44211,95607).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Coenzyme Q10 is chemically similar to menaquinone and might have vitamin K-like procoagulant effects, which could decrease the effects of warfarin.  Details Concomitant use of coenzyme Q10 and warfarin might reduce the anticoagulant effects of warfarin (2128,6048,6199). Four cases of decreased warfarin efficacy thought to be due to coenzyme Q10 have been reported (2128,6048,11048). However, there is some preliminary clinical research that suggests coenzyme Q10 might not significantly decrease the effects of warfarin in patients who have a stable INR (11905).

(Read more about COENZYME Q10)

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use of coleus and anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.  Details In vitro and animal research shows that forskolin, a constituent of coleus, can inhibit platelet aggregation and adhesion (7410,7411,7412).

ANTIHYPERTENSIVE DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, combining coleus with antihypertensive drugs might cause additive blood pressure lowering effects and increase the risk of hypotension.  Details Animal research shows that forskolin, a constituent of coleus, may lower blood pressure (7278,7279,44424,44431).

CALCIUM CHANNEL BLOCKERS Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Theoretically, combining coleus with calcium channel blockers might increase the coronary vasodilatory effects.  Details Forskolin, a constituent of coleus, and calcium channel blockers both cause coronary vasodilatory effects (7278,7279).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking coleus may affect drugs metabolized by CYP2C9 and increase the risk of adverse effects or reduce the effectiveness.  Details Research on the effect of coleus on CYP2C9 is conflicting. Some animal research shows that coleus extract can induce CYP2C9, while in vitro research shows that coleus can inhibit CYP2C9 (91891). Until more is known, advise patients that taking coleus might increase or decrease levels of drugs metabolized by CYP2C9.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking coleus might decrease serum levels of drugs metabolized by CYP3A4.  Details In vitro research shows that coleus can activate the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4 (44399,44412). Although the clinical significance of this is not known, use caution when considering concomitant use of coleus and other drugs affected by these enzymes.

NITRATES Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Theoretically, combining coleus with nitrates might increase the coronary vasodilatory effects.  Details Forskolin, a constituent of coleus, and nitrates both cause coronary vasodilatory effects (7278,7279,44424).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking coleus may affect the metabolism of warfarin and increase the risk of adverse effects or reduce the effectiveness.  Details Some animal research shows that coleus extract can induce cytochrome P450 2C9 (CYP2C9), an enzyme that metabolizes warfarin. However, other in vitro research shows that coleus can inhibit CYP2C9 (91891). Theoretically, taking coleus with drugs metabolized by CYP2C9 might affect drug levels and the risk of adverse effects. Until more is known, advise patients that taking coleus might increase or decrease levels of warfarin.

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(Read more about GOLDTHREAD)

ADENOSINE (Adenocard) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, guarana might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.  Details Guarana contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine (11771). It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests (11770). However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).

ALCOHOL (Ethanol) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, alcohol might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Concomitant use of alcohol can increase caffeine serum concentrations and the risk of caffeine adverse effects. Alcohol reduces caffeine metabolism (6370).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.  Details In vitro and animal research suggests that guarana extract can inhibit platelet aggregation (54378,54388,54435). This effect may be due to the caffeine in guarana, which is also reported to have antiplatelet activity (8028,8029). This interaction has not been reported in humans.

ANTIDIABETES DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Moderate •  Occurrence = Unlikely •  Level of Evidence = B Theoretically, taking guarana with antidiabetes drugs might interfere with blood glucose control.  Details Some conflicting reports claim that caffeine, a constituent of guarana, might increase or decrease blood sugar (6024,8646).

BETA-ADRENERGIC AGONISTS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use might increase the clinical effects of beta-adrenergic agonists.  Details Guarana contains caffeine. Theoretically, concomitant use of large amounts of caffeine might increase cardiac inotropic effects of beta-agonists (15).

CARBAMAZEPINE (Tegretol) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of carbamazepine and increase the risk for convulsions.  Details Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when given to animals in doses above 400 mg/kg (23559,23561). Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine two-fold in healthy individuals (23562).

CIMETIDINE (Tagamet) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Likely •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine in guarana.  Details Guarana contains caffeine. Cimetidine decreases the rate of caffeine clearance by 31% to 42% (11736).

CLOZAPINE (Clozaril) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, guarana might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.  Details Guarana contains caffeine. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day inhibit clozapine metabolism (5051). Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to the interaction between clozapine and caffeine (13741).

CONTRACEPTIVE DRUGS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in guarana.  Details Guarana contains caffeine. Oral contraceptives decrease the rate of caffeine clearance by 40% to 65% (2714,11737).

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Caffeine is metabolized by the CYP1A2 enzyme. Theoretically, drugs that inhibit CYP1A2 may decrease the rate of caffeine clearance and increase caffeine levels (5051,11741).

DIPYRIDAMOLE (Persantine) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, guarana might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.  Details Guarana contains caffeine. Caffeine might inhibit dipyridamole-induced vasodilation (11770,11772). It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests (11770). Methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing (11771).

DISULFIRAM (Antabuse) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, disulfiram might increase the risk of adverse effects from caffeine.  Details In human research, disulfiram decreases the clearance and increases the half-life of caffeine (11840).

DIURETIC DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, using guarana with diuretic drugs might increase the risk of hypokalemia.  Details Guarana contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump (23579,37905,37953,38003,38034). Diuretics can also lower potassium levels.

EPHEDRINE Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use might increase the risk for stimulant adverse effects.  Details Guarana contains caffeine. Use of ephedrine with caffeine can increase the risk of stimulatory adverse effects. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death (1275,6486,10307).

ESTROGENS Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, estrogens might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Estrogen inhibits caffeine metabolism (2714).

ETHOSUXIMIDE (Zarontin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of ethosuximide and increase the risk for convulsions.  Details Guarana contains caffeine. Animal research shows that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide (23560). This effect has not been observed in humans.

FELBAMATE (Felbatol) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of felbamate and increase the risk for convulsions.  Details Guarana contains caffeine. Animal research shows that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate (23563). This effect has not been observed in humans.

FLUCONAZOLE (Diflucan) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, fluconazole might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Fluconazole decreases caffeine clearance by approximately 25% (11022).

FLUTAMIDE (Eulexin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, guarana might increase the levels and adverse effects of flutamide.  Details Guarana contains caffeine. In vitro evidence shows that caffeine can inhibit the metabolism of flutamide (23553). However, this effect has not been reported in humans.

FLUVOXAMINE (Luvox) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Fluvoxamine reduces caffeine metabolism (6370).

LITHIUM Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, abrupt guarana withdrawal might increase the levels and adverse effects of lithium.  Details Guarana contains caffeine. Theoretically, abrupt caffeine withdrawal might increase serum lithium levels. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal (609,610).

METFORMIN (Glucophage) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, metformin might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Animal research shows that metformin can reduce caffeine metabolism (23571). However, this effect has not been reported in humans.

METHOXSALEN (Oxsoralen) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, methoxsalen might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Methoxsalen can reduce caffeine metabolism (23572).

MEXILETINE (Mexitil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, mexiletine might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Mexiletine can decrease caffeine elimination by 50% (1260,11741).

MONOAMINE OXIDASE INHIBITORS (MAOIs) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the risk of a hypertensive crisis.  Details Guarana contains caffeine. Caffeine has been shown to inhibit MAO-A and -B in laboratory studies (37724,37877,37912,38108). Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis (15). In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension (91086). Hypertension was resolved after the patient switched to drinking decaffeinated coffee.

NICOTINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, concomitant use might increase the risk of hypertension.  Details Guarana contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly (36549).

PENTOBARBITAL (Nembutal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, guarana might decrease the effects of pentobarbital.  Details Guarana contains caffeine. In vivo evidence suggests that caffeine can negate the hypnotic effects of pentobarbital in humans (13742). However, animal research suggests that guarana does not alter the hypnotic effect of pentobarbital (54419).

PHENOBARBITAL (Luminal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of phenobarbital and increase the risk for convulsions.  Details Guarana contains caffeine. Animal research shows that caffeine can decrease the anticonvulsant activity of phenobarbital (23558,23559,23561). The exact mechanism of this interaction is unclear.

PHENOTHIAZINES Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, phenothiazines might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Phenothiazines can reduce the metabolism of caffeine by inhibiting cytochrome P450 1A2 (CYP1A2) (23573,23574).

PHENYLPROPANOLAMINE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure (11738). Phenylpropanolamine also seems to increase caffeine serum levels (13743).

PHENYTOIN (Dilantin) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of phenytoin and increase the risk for convulsions.  Details Guarana contains caffeine. Animal research shows that caffeine can decrease the anticonvulsant activity of phenytoin (23559,23561). The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

PIOGLITAZONE (Actos) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might increase the levels and clinical effects of pioglitazone.  Details Guarana contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone (108812). However, the exact mechanism of this interaction is unclear.

QUINOLONE ANTIBIOTICS Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Theoretically, concomitant use might increase serum caffeine concentrations and the risk of adverse effects. Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting the cytochrome P450 1A2 enzyme (606,607,608,23554,23555,23556).

RILUZOLE (Rilutek) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.  Details Guarana contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce the metabolism of one or both agents (11739).

STIMULANT DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, concomitant use might increase stimulant adverse effects.  Details Guarana contains caffeine. Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of adverse effects (11832).

TERBINAFINE (Lamisil) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, terbinafine might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. Terbinafine decreases the clearance of intravenous caffeine by 19% (11740).

THEOPHYLLINE Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = D Theoretically, guarana might increase the levels and adverse effects of theophylline.  Details Guarana contains caffeine. Large amounts of caffeine might decrease theophylline clearance by 23% to 29% (11741).

TIAGABINE (Gabitril) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might increase the levels and adverse effects of tiagabine.  Details Guarana contains caffeine. Animal research shows that chronic caffeine administration can increase the serum concentrations of tiagabine. However, concomitant use does not seem to reduce the antiepileptic effects of tiagabine (23561).

TICLOPIDINE (Ticlid) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = D Theoretically, ticlopidine might increase the levels and adverse effects of caffeine.  Details Guarana contains caffeine. In vitro evidence shows that ticlopidine can inhibit the metabolism of caffeine (23557). However, this interaction has not been reported in humans.

VALPROATE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, guarana might reduce the effects of valproate and increase the risk for convulsions.  Details Guarana contains caffeine. Animal research shows that caffeine can decrease the anticonvulsant activity of valproate (23558,23559,23561,37882). The exact mechanism of this interaction is unclear.

VERAPAMIL (Calan, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, verapamil might increase the levels and adverse effects of caffeine.  Details Verapamil increases plasma caffeine concentrations by 25% (11741).

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ACETAZOLAMIDE Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, willow bark might result in additive adverse effects associated with acetazolamide.  Details Willow bark contains salicin, a plant salicylate. Human case reports suggests that a combination of acetazolamide and salicylate increases unbound plasma levels of acetazolamide, as well as adverse effects related to acetazolamide (86481).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, willow bark might increase the risk of bleeding when taken with anticoagulant/antiplatelet drugs.  Details Willow bark has antiplatelet effects, but less so than aspirin (12810).

ASPIRIN Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, willow bark might increase the effects and adverse effects of aspirin.  Details Willow bark contains salicin, a plant salicylate. It might have an additive effect when taken with other salicylate-containing drugs such as aspirin (12808).

CHOLINE MAGNESIUM TRISALICYLATE (Trilisate) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, willow bark might increase the effects and adverse effects of choline magnesium trisalicylate.  Details Willow bark contains salicin, a plant salicylate. It might have an additive effect when taken with other salicylate-containing drugs such as choline magnesium trisalicylate (12808).

SALSALATE (Disalcid) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = D Theoretically, willow bark might increase the effects and adverse effects of salsalate.  Details Willow bark contains salicin, a plant salicylate. It might have an additive effect when taken with other salicylate-containing drugs such as salsalate (12808).

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General ...Orally, berberine is generally well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain and distension, constipation, diarrhea, flatulence, nausea, vomiting.
Intravenously: Facial flushing, painful swelling at the injection site.
Serious Adverse Events (Rare):
Intravenously: Ventricular tachycardia consistent with torsades de pointes.

Cardiovascular ...In four of 12 patients with refractory congestive heart failure, intravenous infusion of berberine at a rate of 0. 2 mg/kg per minute caused ventricular tachycardia consistent with torsades de pointes (33642).

Dermatologic ...When administered intravenously, berberine can cause painful swelling at the injection site or facial flushing (34330). In three of 12 people injected subcutaneously with berberine, permanent hyperpigmentation at the injection site occurred (33698).
Orally, berberine may cause rash, but this event appears to be rare (34285,110106).

Endocrine ...Orally, berberine may cause hypoglycemia (111363).

Gastrointestinal ...Orally, berberine may cause diarrhea, constipation, flatulence, nausea, vomiting, abdominal pain, abdominal distention, gastroesophageal reflux, and bitter taste (33648,33689,34245,34247,34285,91953,99920,99921,103194,103197)(110106,111363,111699,113462,114769).

Hepatic ...Orally, berberine may occasionally cause an increase in transaminases (99921,103194). However, meta-analyses have found no significant effect of berberine on alanine aminotransferase (ALT) or aspartate aminotransferase (AST) (104508,111363).

Musculoskeletal ...Reports of mild muscle pain and muscle weakness have been reported following the use of a combination product containing berberine, policosanol, red yeast rice, folic acid, coenzyme Q10, and astaxanthin (34283). It is unclear if these effects are due to berberine or other constituents.

Neurologic/CNS ...Orally, berberine may cause dizziness, drowsiness, fatigue, and headache (33648,99921,113462).

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General ...Orally, coenzyme Q10 is generally well tolerated. In clinical studies, no serious adverse effects have been reported.
Most Common Adverse Effects:
Orally: Gastrointestinal side effects such as appetite suppression, diarrhea, epigastric discomfort, heartburn, nausea, and vomiting. These generally occur in less than 1% of patients. Some of these adverse effects can be minimized if daily doses above 100 mg are divided.

Cardiovascular ...Palpitations have been reported as being possibly associated with coenzyme Q10 treatment (89421). Death due to myocardial infarction occurred in one Parkinson disease patient taking coenzyme Q10; causality is unclear (15395).

Dermatologic ...Two of 143 participants in a case series reported skin itching after starting treatment with oral coenzyme Q10 (6047). Allergic rash has also been reported (6409,11872). An itching exanthema was seen in two heart failure patients treated with intravenous coenzyme Q10 (44284).

Gastrointestinal ...Gastrointestinal side effects of coenzyme Q10 have included nausea (3365,6409,8907,10152,43982,44172,44179,44330,89421,109392), vomiting (3365,10152,44330,89421), epigastric discomfort (3365,44179,44330,89421), constipation (109392), diarrhea (44179,92904,89421,109392), stomach upset (8940,12170,109387,109388,109392), loss of appetite (2121), heartburn (2121,44179,109392), and flatulence (43982), although this occurs in less than 1% of patients. In one clinical study, gastrointestinal bleeding in association with angiodysplasia has been reported to be possibly related to coenzyme Q10 treatment (89421).

Genitourinary ...An uncomplicated urinary infection was reported in a patient taking oral coenzyme Q10 (nanoQuinon, MSE Pharmazeutika) (44020).

Hematologic ...Thrombocytopenia was noted in one patient treated with oral coenzyme Q10 (44296); however, other factors (viral infection, other medications) may have been responsible for this adverse effect.

Musculoskeletal ...Increased plasma creatine kinase with high-intensity exercise has been reported in patients taking coenzyme Q10 (44303). Muscle pain has been reported rarely in one clinical trial (109392).

Neurologic/CNS ...Headache and dizziness have been reported in human research (3365,11872,43982,44330,109392). Insomnia has been reported as being possibly associated with coenzyme Q10 treatment (89421). Cognitive decline, depression, and sudden falls were reported rarely in a clinical trial of patients with Huntington disease (8940). Increased lethargy was reported for one patient treated with oral coenzyme Q10 (44042). Feeling of internal trembling has been reported in a clinical trial for one patient treated with coenzyme Q10 (44020).

Ocular/Otic ...Visual sensitivity to light has been reported for a patient treated with coenzyme Q10. However, the association of this effect with coenzyme Q10 treatment was not clear (6409).
A burning sensation has been reported for 10% of patients treated with a topical eye solution containing coenzyme Q10 and alpha-tocopheryl polyethylene glycol 1000 succinate following cataract surgery (44228).

Psychiatric ...Worsening depression has been reported as being possibly associated with oral coenzyme Q10 treatment (89421).

Pulmonary/Respiratory ...Drug-induced pneumonitis was diagnosed in a 61 year-old woman who had been taking coenzyme Q10 and perilla leaf extract for two months (43978). Symptoms improved after she stopped taking the supplements and began taking oral prednisone. Causation from coenzyme Q10 was unclear.

Other ...In a case report, a naval aviator using a supplement containing coenzyme Q10 and niacin had reduced G tolerance (44186). G tolerance was regained with cessation of the supplement.

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General ...Orally, intravenously, ophthalmologically, and by inhalation, coleus seems to be well tolerated.
Most Common Adverse Effects:
Orally: Constipation, diarrhea, nausea, vomiting.
Intravenously: Flushing, hypotension, tachycardia.
Ophthalmologically: Conjunctival hyperemia, stinging eyes.
Inhalation: Irritation of the respiratory tract, restlessness, tremor.

Cardiovascular ...Intravenously, the coleus constituent, forskolin, can cause tachycardia, flushing and hypotension (7279,44424,44431).

Dermatologic ...Two cases of contact dermatitis have been reported following airborne exposure to coleus (44426,44418).

Gastrointestinal ...Orally, coleus can cause dose-related diarrhea and other gastrointestinal symptoms. Increased bowel movements and loose stools have been reported in 1 of 15 patients taking coleus extract in a clinical trial (91885). Some retrospective evidence reports about a 10% rate of gastrointestinal adverse effects from oral coleus use; 81% of these adverse effects were related to diarrhea. Other reported adverse effects which occurred at a much lower rate, include nausea, vomiting, and/or constipation. Gastrointestinal effects appear to be dose-related; those taking less than 250 mg of coleus extract did not report any diarrhea, while all patients taking 1000 mg of coleus extract reported diarrhea (100851).

Neurologic/CNS ...Inhalation of forskolin, a constituent of coleus, can cause tremor and restlessness (7281).

Ocular/Otic ...Ophthalmologically, forskolin, a constituent of coleus, can cause stinging of the eyes and conjunctival hyperemia (7283).

Pulmonary/Respiratory ...Inhalation of forskolin, a constituent of coleus, can cause throat and upper respiratory tract irritation, and mild to moderate cough (7281).

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General ...No adverse effects have been reported in adults. However, a thorough evaluation of safety outcomes has not been conducted.

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General ...Orally, guarana is typically well tolerated when used in moderation. Due to its caffeine content, use of large doses may be unsafe.
Most Common Adverse Effects:
Orally: Stomach burning and nausea.

Cardiovascular ...Orally, a case of premature ventricular contraction has been reported for a 51-year-old female who used guarana as part of a multi-ingredient herbal product (54372).
Guarana contains caffeine. Although acute administration of caffeine can increase blood pressure, regular consumption does not seem to increase either blood pressure or pulse, even in mildly hypertensive patients (1451,1452,2722). Also, epidemiological research suggests there is no association between caffeine consumption and increased incidence of hypertension. Habitual coffee consumption doesn't seem to be related to hypertension, but habitual consumption of sugared or diet cola is associated with development of hypertension (13739).
Combining ephedra with guarana can increase the risk of adverse effects. Cases of hypertension and chest pain have been reported for patients who took products containing guarana and ephedra (8644,54376). A case of cerebral infarction has also been reported for a patient consuming ephedra extract and guarana (48746). There is also a report of ischemic stroke in an athlete who consumed ephedra 40-60 mg, creatine monohydrate 6 grams, caffeine 400-600 mg, and a variety of other supplements daily for six weeks (1275).

Dermatologic ...Guarana contains caffeine. There are several case reports of urticaria after caffeine ingestion (36546,36448,36475).

Endocrine ...Guarana contains caffeine. Some evidence shows caffeine is associated with fibrocystic breast disease, breast cancer, and endometriosis; however, this is controversial since findings are conflicting (8043). Restricting caffeine in people with fibrocystic breast conditions doesn't seem to affect breast nodularity, swelling, or pain (8996). A population analysis of the Women's Health Initiative observational study has found no association between consumption of caffeine-containing beverages and the incidence of invasive breast cancer in models adjusted for demographic, lifestyle, and reproductive factors (108806). Also, a dose-response analysis of 2 low-quality observational studies has found that high consumption of caffeine is not associated with an increased risk of breast cancer (108807).
Although the effects of guarana alone are not clear, the combination of guarana along with ephedra has been reported to cause increased blood glucose levels and decreased blood levels of potassium (54376).

Gastrointestinal ...Orally, guarana can cause a sensation of burning in the stomach and vomiting (54414,91487). These effects may be due to caffeine in guarana. Orally, caffeine can cause gastric irritation, nausea, and vomiting (11832,11838,13735). In infants, caffeine may also cause feeding intolerance and gastrointestinal irritation (6023).

Immunologic ...Guarana contains caffeine. When taken orally, caffeine can cause anaphylaxis in sensitive individuals, although true IgE-mediated caffeine allergy seems to be relatively rare (11315).

Musculoskeletal ...In a clinical trial of guarana extract, one person abandoned treatment due to symptoms of arthritis with edema. It is not clear if this adverse effect is due to guarana (91487).
Cases of rhabdomyolysis and myoglobinuria have been reported in individuals that have taken products containing guarana in combination with ephedra and other herbal products. These adverse effects are thought to be related to the caffeine content of guarana (19154,36466).
Epidemiological evidence regarding the relationship between caffeine use and the risk for osteoporosis is contradictory. Caffeine can increase urinary excretion of calcium (2669,10202,11317). Women identified with a genetic variant of the vitamin D receptor appear to be at an increased risk for the detrimental effect of caffeine on bone mass (2669). However, moderate caffeine intake, less than 300 mg per day, does not seem to significantly increase osteoporosis risk in most postmenopausal women with normal calcium intake (2669,6025,10202,11317).

Neurologic/CNS ...Orally, guarana can cause dizziness (91483). The caffeine in guarana can cause insomnia (especially in children), nervousness, restlessness, dizziness, tremors, delirium, and convulsions. Other symptoms include headache, anxiety, and agitation (10755,11832,11838,13735,108016).
Taking guarana with ephedra can cause insomnia, irritability, dizziness, and headache (3719). The combination of ephedra and caffeine in guarana might also increase the risk of adverse effects such as jitteriness, seizures, and temporary loss of consciousness (2729,21015).

Ocular/Otic ...Guarana contains caffeine. When taken orally, caffeine can cause ringing in the ears (11832,11838,13735).

Psychiatric ...In a clinical trial, depression was reported by one person taking guarana extract (91483).

Renal ...Guarana contains caffeine. When taken orally, caffeine can cause diuresis (11832,11838,13735).

Other ...Guarana contains caffeine. The existence or clinical importance of caffeine withdrawal is controversial. Some researchers think that if it exists, it appears to be of little clinical significance (11839). Other researchers suggest symptoms such as headache; tiredness and fatigue; decreased energy, alertness, and attentiveness; drowsiness; decreased contentedness; depressed mood; difficulty concentrating; irritability; and lack of clear-headedness are typical of caffeine withdrawal (13738). Withdrawal symptoms such as delirium, nausea, vomiting, rhinorrhea, nervousness, restlessness, anxiety, muscle tension, muscle pains, and flushed face have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects. Clinically significant symptoms caused by caffeine withdrawal may be uncommon (2723,11839).

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General ...Orally, willow bark seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, dyspepsia, heartburn, and vomiting. May cause itching and rash in sensitive individuals.
Serious Adverse Effects (Rare):
Orally: Gastrointestinal bleeding and renal impairment. May cause serious allergic reactions, including anaphylaxis, in people who are allergic to aspirin.

Cardiovascular ...In one clinical trial, a single patient withdrew from the study investigating oral willow bark due to blood pressure instability that the authors determined was 'possibly' related to treatment (12804).

Dermatologic ...Orally, willow bark may cause itching and rash in some people due to allergy (6456,12474,12475,12804,86459).

Gastrointestinal ...Orally, willow bark extract can cause gastrointestinal adverse effects, but these appear to be less frequent than those caused by NSAIDs. Examples include diarrhea, heartburn, vomiting, and dyspepsia (12474,12475,12804,86459). In a case report of a child, severe gastrointestinal bleeding occurred following use of a specific syrup (FreddoBaby), which contained ribwort plantain, licorice, willow bark, black elder, meadowsweet, and propolis. The adverse effect was attributed to salicylate content of the syrup. This product has since been withdrawn from the market (86477).

Immunologic ...Orally, willow bark may cause serious allergic reactions, including anaphylaxis, in people who are allergic to aspirin (10392)

Neurologic/CNS ...Orally, willow bark may cause headache and dizziness (12804). In a clinical trial evaluating a combination product containing willow bark, black cohosh, sarsaparilla, poplar bark, and guaiac wood (Reumalex), severe headaches occurred (35946).

Ocular/Otic ...Orally, symptoms of allergy to willow bark have included swollen eyes (6456).

Renal ...Salicylates can inhibit prostaglandins, which can reduce renal blood flow (12805). Salicin can cause renal papillary necrosis (12806). The risk for toxicity is greater with high acute doses or chronic use (12805).

(Read more about WILLOW BARK)