AKL1 by AKL Technologies Ltd.

POSSIBLY EFFECTIVE

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

POSSIBLY INEFFECTIVE

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

INSUFFICIENT RELIABLE EVIDENCE to RATE

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

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POSSIBLY EFFECTIVE

• Anxiety. Oral ginkgo seems to modestly reduce anxiety symptoms. Details: Clinical research shows that taking a specific ginkgo extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) for 4 weeks can modestly reduce symptoms of anxiety in a greater percentage of adults with generalized anxiety disorder or adjustment disorder with anxious mood when compared with placebo. After 4 weeks of treatment, a reduction in anxiety rating score of at least 50% was seen in 44% of patients treated with 480 mg daily, 39% of patients treated with 240 mg daily, and 22% of patients treated with placebo (15578). It is unclear whether these effects would persist when taken for longer than 4 weeks. This study was also included in a meta-analysis that performed indirect comparisons of multiple herbs for the treatment of anxiety. This analysis suggests that taking ginkgo may reduce anxiety scores modestly more than kava (110711). However, the interpretation of these results is limited by the small amount of data available for ginkgo.
• Dementia. Oral ginkgo 240 mg seems to improve symptoms of various types of dementia, but lower doses are not always effective. Oral ginkgo does not seem to prevent or slow down the progression of dementia. Details: Most evidence shows that higher doses of a specific ginkgo extract (EGb761) modestly improve symptoms of Alzheimer, vascular, or mixed dementias. Meta-analyses of clinical research in patients with dementia show that taking ginkgo, usually 240 mg daily for 24 weeks, modestly improves cognition and activities of daily living when compared with placebo. When analyses pooled studies testing low-dose (120 mg) and high-dose (240 mg) ginkgo together, the benefit was not always present (87855,87819,87851,87866,88006,89713,102183,102185,102186,103572)(111333). Although most clinical trials show benefit, there are some clinical trials with conflicting findings, suggesting inconsistent and unpredictable effects (16637,87726). There has been some debate about whether ginkgo is more effective in dementia patients who have neuropsychiatric symptoms. Most clinical research shows that this is not the case. However, high-dose ginkgo 240 mg daily seems to modestly relieve most neuropsychiatric symptoms other than psychosis (17717,87794,87897,102185,102187). Few clinical studies compare ginkgo leaf extract to conventional drugs such as cholinesterase inhibitors. Some preliminary comparative studies show that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 160-240 mg daily for 22-24 weeks seems to be comparable to donepezil (Aricept) 5-10 mg daily for mild to moderate Alzheimer disease (14499,87826). Similarly, a clinical study in patients with Alzheimer disease or mild cognitive impairment shows that taking ginkgo extract 150 mg three times daily for 6 months seems to be comparable to donepezil 5 mg daily for improvement of cognitive scores (106611). However, indirect comparisons suggest that ginkgo leaf extract might be less effective than the conventional drugs donepezil, tacrine (Cognex), rivastigmine (Exelon), and other cholinesterase inhibitors (6224,6490,11981,89710). Also, some studies show that taking ginkgo in combination with conventional medications for 12-24 weeks does not improve cognitive scores by a clinically meaningful extent when compared with conventional medications alone (95902,106611). However, a meta-analysis of 17 mostly small, low quality clinical studies in patients with Alzheimer disease, that includes some of these studies, shows that taking ginkgo in combination with donepezil for 3-9 months modestly improves cognitive scores when compared with donepezil alone. Adding ginkgo may also improve activities of daily living scores (111332). However, the validity of these findings is limited by the heterogeneity of the included studies, which utilized various doses and forms of ginkgo. Ginkgo does not appear to be beneficial for preventing or slowing the progression of dementia. Epidemiologic research shows that taking ginkgo extract is not associated with a decreased risk of developing dementia in elderly patients with memory impairment (14812). Three large-scale clinical trials also show that taking ginkgo extract 120 mg twice daily does not reduce the risk of developing all-cause dementia or Alzheimer disease in elderly patients with normal cognitive function or in those with mild cognitive impairment (16634,87848,87904). In addition, taking ginkgo extract does not seem to prevent disease progression in Alzheimer patients (89713). Most of the clinical studies on the effectiveness of ginkgo leaf for dementia have used the standardized extracts EGb 761 (Dr. Willmar Schwabe Pharmaceuticals and Ipsen) and LI 1370 (Lichtwer Pharma). These two extracts are similar and prepared to contain approximately 24% to 25% flavone glycosides and 6% terpene lactones. Other products with similar ingredients include Ginkai (Lichtwer Pharma), Ginkgo 5 (Pharmline), Ginkgold and Ginkgo (Nature's Way), and Quanterra Mental Sharpness (Warner-Lambert).
• Hearing loss. Intravenous ginkgo appears to improve hearing loss when used in conjunction with corticosteroids. The effectiveness of oral ginkgo is unclear. Details: A meta-analysis of randomized controlled trials (RCTs) in adults with sudden hearing loss shows that using intravenous ginkgo leaf extract 40-175 mg daily, in addition to corticosteroids, for 5-14 days increases clinical cure rates by 1.3 times that of corticosteroids alone. Ginkgo leaf in combination with corticosteroids also improved hearing sensitivity (107360). Another meta-analysis of 27 mostly low-quality RCTs in patients with sudden hearing loss, that includes some of the same studies as the prior analysis, shows that adding ginkgo extract to usual care for 1-14 days leads to improvement or no further deterioration in 91% of patients when compared with 75% of patients receiving usual care (111339). However, the interpretation of these results is limited by unclear ginkgo dosing and inclusion of studies that administered ginkgo orally, as an injection, or unknown route. In addition, usual care treatments were not described. In addition, one clinical study in patients with short-term idiopathic hearing loss shows that oral ginkgo leaf extract 120 mg twice daily for 8 weeks might improve hearing recovery rates when compared with ginkgo leaf extract 12 mg twice daily (8543). However, there was a high spontaneous recovery rate in both groups, so it is unclear how much benefit, if any, can be attributed to ginkgo leaf extract.
• Premenstrual syndrome (PMS). Oral ginkgo seems to reduce symptoms of PMS. Details: Taking ginkgo leaf extract orally 80 mg twice daily or 40 mg three times daily seems to produce significant relief in breast tenderness and other physical and psychological symptoms associated with PMS when started during the 16th day of the menstrual cycle and continued until the 5th day of the following cycle for up to two cycles (6229,87839). Specific ginkgo leaf extracts that have been assessed for this condition include Ginko T.D. (Tolidaru Pharmaceuticals) and EGb 761, which is an ingredient in several commercial products including Tebonin (Dr. Willmar Schwabe Pharmaceuticals), Tanakan (Ipsen), and Quanterra Mental Sharpness (Warner-Lambert).
• Schizophrenia. Oral ginkgo seems to reduce total and negative symptoms of schizophrenia, and may be beneficial for reducing antipsychotic-associated adverse effects. Details: Taking a standardized ginkgo leaf extract EGb 761 (Yi Kang Ning, Yang Zi Jiang Pharmaceuticals Ltd.), 120-360 mg orally daily in addition to standard antipsychotic medications (such as olanzapine, clozapine, or haloperidol) for 8-16 weeks, can reduce total and negative symptoms of schizophrenia when compared to treatment with antipsychotic medications alone (87844,95901). Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that ginkgo extract at doses of 120-360 mg daily is weakly recommended for adjunctive use in schizophrenia, primarily for negative symptoms (110318). Treatment with ginkgo leaf extract might also reduce anticholinergic side effects such as thirst and constipation and adverse behavioral, cardiovascular, and nerve symptoms associated with antipsychotic treatment (87708,95901). Additional clinical research is needed to determine the role of ginkgo on antipsychotic-associated adverse effects.
• Stroke. Oral and intravenous ginkgo seem to improve recovery from stroke; intravenous ginkgo might be more effective. Details: While some individual studies show conflicting results, meta-analyses of small, low-quality clinical trials in patients recovering from ischemic stroke show that oral or intravenous ginkgo extract along with conventional therapy seems to improve neurologic function and activities of daily living scores, but does not improve quality of life or reduce the risk of recurrent stroke or death, when compared with conventional therapy alone (14435,102883,102884,107452). One meta-analysis shows that intravenous ginkgo extract is associated with greater improvements in these measures than oral ginkgo extract (102884). Ginkgo diterpene lactone meglumine (GDLM) is a derivative of ginkgo composed of active ingredients ginkgolides A, B, and K that has been investigated for the treatment of acute ischemic stroke both as monotherapy and in combination with thrombolysis. A very large clinical trial in adults with moderate acute ischemic stroke shows that an intravenous infusion of GDLM 25 mg initiated within 48 hours of symptom onset for 14 days increases the proportion of patients achieving a favorable outcome, defined as a score of 0 or 1 on the modified Rankin Scale (mRS) on day 90, by 15% when compared with placebo (111693). Additionally, a meta-analysis shows that combination therapy with GDLM and tissue plasminogen activator (rTPA) is associated with greater improvements than conventional treatments alone or other traditional Chinese herbal medicines that contain ginkgo (i.e. ginaton, danhong, xueshuantong, and shuxuening injections). This specific formulation also appears to be more effective than intravenous ginkgolides or ginkgolide B; however, investigators did not provide a statistical comparison of outcomes between groups, limiting the validity of this finding (108610). Another meta-analysis shows that intravenous administration of ginkgo leaf extract plus dipyridamole 10-40 mL daily for 14-30 days along with conventional therapy also improves neurologic function and activities of daily living when compared with conventional therapy alone (102882). In patients not treated with thrombolytics, a small clinical study in adults in China shows that administering ginkgo diterpene lactone meglumine 25 mg intravenously daily for 14 days, starting within 48 hours after an ischemic stroke, in addition to aspirin 100 mg daily for 90 days, led to improvement in scores related to stroke severity or the degree of disability at 90 days in 94% of patients when compared with 83% of patients treated with aspirin alone (111340). However, the patients in this study had minor or moderate strokes; these results may not apply to patients with more severe strokes. In patients with hemorrhagic stroke, preliminary clinical research shows that daily intravenous administration of ginkgo extract (Taiwan Jisheng Chemical Pharmaceutical Co., Ltd.) 17.5 grams for 2 weeks, in conjunction with routine treatment and intravenous oxiracetam 6 grams, reduces cerebral edema and bleeding and modestly improves recovery of neurological and cognitive function and activities of daily living when compared with oxiracetam plus routine care or routine care alone (103573). Higher quality studies are still needed to confirm these results.
• Tardive dyskinesia. Oral ginkgo seems to reduce the severity of tardive dyskinesia in schizophrenic patients being treated with antipsychotic medications. Details: Clinical research shows that taking a specific ginkgo extract called EGb 761 (Yi Kang Ning, Yang Zi Jiang Pharmaceuticals Ltd.) 80 mg three times daily for 12 weeks can reduce the severity of tardive dyskinesia by at least 30% when compared with placebo in schizophrenic patients being treated with antipsychotic medications (87864).
• Vascular dementia. Oral ginkgo extract seems to modestly improve scores related to cognitive function in patients with this condition. Details: A small clinical study in patients with vascular dementia shows that taking a specific extract of ginkgo EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 240 mg daily for 24 weeks modestly improves scores related to cognitive function, neuropsychiatric symptoms, and activities of daily living when compared with placebo (17191). A preliminary open-label clinical study in patients aged 50 years or older in China shows that taking the same ginkgo extract 240 mg daily for 24 weeks, starting within 7-14 days after an ischemic stroke, modestly improves scores related to cognitive function and mental health, but not neuropsychiatric symptoms, when compared with standard care (111335). However, the patients in this study had minor strokes; these results may not apply to patients with more severe strokes. Ginkgo has also been evaluated in combination with other ingredients to treat vascular dementia. A small clinical study in patients aged 60 years or older with vascular dementia shows that taking a supplement containing extracts of ginkgo, Panax ginseng, and saffron 60 mg three times daily for 16 weeks modestly improves some cognitive function scores, caregiver assessed activities of daily living, and patient-reported quality of life. However, these effects were not maintained after patients stopped taking the supplement (111336).
• Vertigo. Oral ginkgo seems to improve symptoms of vertigo in people with vestibular disorders. It is unclear if it is beneficial for vertigo caused by cerebral arteriosclerosis. Details: Taking ginkgo leaf extract 120-160 mg daily orally seems to improve symptoms of vertigo and equilibrium disorders (5721,6220,6221,107359,108608). There is evidence from two clinical studies that ginkgo leaf extract (EGb 761) for 3 months is significantly more effective than placebo (6220), and possibly as effective as betahistine, for improving vertigo and dizziness caused by vascular vestibular disorders and vestibular disorders of unknown origin (6220,6221). However, adding balance training to treatment with ginkgo leaf extract (EGb 761) orally 80 mg twice daily for 3 months is no better than taking ginkgo leaf extract alone (107359). Ginkgo has also been evaluated in patients with vertigo caused by mild cerebral arteriosclerosis. A clinical study in this population shows that taking oral ginkgo leaf extract (Zhejiang Jiu Xu Pharmaceutical Co, Ltd) 40 mg three times daily for 6 weeks improves scores of traditional Chinese medicine symptom pattern, specifically dizziness, blurry vision, headache, and amnesia, but does not impact Dizziness Handicap Inventory scores, when compared with naoxinqing (NXQ), a standardized herbal product that contains Japanese persimmon leaf extract (108608). The validity of this study is limited due to the lack of comparison to placebo or an accepted conventional treatment.

POSSIBLY INEFFECTIVE

• Age-related cognitive decline. Most research shows that oral ginkgo does not improve symptoms of age-related cognitive impairment. Details: While some preliminary clinical research shows a modest benefit of ginkgo leaf extract on memory and cognitive function in patients with age-related memory or thinking impairment (5717,6216,89712), most clinical research shows that taking ginkgo leaf extract orally does not improve memory or attention in elderly individuals with normal mental function (5718,8586,8587,8588,87848). Clinical research also shows that taking a standardized ginkgo leaf extract (Thorne Research Inc.) 240 mg daily for 3.5 years does not reduce the risk of developing age-related cognitive impairment in elderly patients aged 85 years and older who have normal cognitive function (16635).
• Antidepressant-induced sexual dysfunction. Most research shows that oral ginkgo does not improve symptoms of sexual dysfunction in people using antidepressants. Details: Although some preliminary clinical research shows that taking ginkgo leaf extract orally might help sexual dysfunction caused by antidepressant therapy (3965,3967), subsequent research indicates that it not likely to be beneficial (207,3966,3969,10893,14383).
• Cardiovascular disease (CVD). Oral ginkgo does not seem to prevent CVD. Details: A large-scale randomized trial shows that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 240 mg daily orally for an average of 6.1 years does not reduce the risk of myocardial infarction, angina, stroke, CVD-related hospitalization, or mortality in elderly patients when compared with placebo (17402).
• Chemotherapy-related cognitive impairment. Oral ginkgo does not seem to improve symptoms of cognitive impairment in people using chemotherapy. Details: Clinical research shows that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 60 mg twice daily, starting prior to the second cycle of chemotherapy and continuing until one month after chemotherapy completion, does not prevent chemotherapy-related cognitive dysfunction when compared with placebo in chemotherapy-naïve breast cancer patients (89701).
• Hypertension. Oral ginkgo does not seem to reduce blood pressure in older, hypertensive patients. Details: Clinical research shows that taking a standardized ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 240 mg daily for up to 6 years does not reduce blood pressure when compared with placebo in hypertensive patients aged 75 years or older (87853).
• Multiple sclerosis (MS). Most research shows that oral ginkgo does not improve symptoms of MS. Details: Most clinical research shows that taking ginkgo leaf extract or ginkgolide B, a constituent of ginkgo leaf extract, does not improve cognition or disability in patients with MS (87739,87787,87903,87947). However, a single preliminary clinical study shows that taking a standardized ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) may improve processing speed when compared with placebo in patients with multiple sclerosis (89705).
• Tinnitus. Most research shows that oral ginkgo does not improve symptoms of tinnitus. Details: Taking ginkgo leaf extract orally does not seem to improve symptoms of tinnitus. Although some studies have shown benefit, the majority of the clinical evidence indicates that ginkgo leaf extract is not consistently effective for patients with tinnitus (221,910,5721,6218,6219,9871,87754,87901,110093,111337)(111513).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Age-related macular degeneration (AMD). It is unclear if oral ginkgo is beneficial in AMD. Details: Preliminary clinical research suggests that taking a specific ginkgo leaf extract (EGb 761) 60-240 mg orally in divided doses for up to 6 months might improve symptoms of AMD (6227,6228,11797). There is limited evidence that ginkgo leaf extract might significantly improve distance vision in patients with AMD (6227).
• Aging. Although there has been interest in using oral ginkgo for aging, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Allergic rhinitis (hay fever). Topical ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with seasonal allergic conjunctivitis shows that applying two drops of specific eye drops (Trium, SOOFT) containing ginkgo extract 0.05% and hyaluronic acid 0.15%, three times daily for one month can decrease redness by 80%, discharge by 40%, and swelling by 10% when compared to using eye drops with hyaluronic acid alone (87829).
• Altitude sickness. Research on the use of oral ginkgo for altitude sickness is conflicting. Details: Some research shows that taking ginkgo extract 80-120 mg twice daily for 4 days before the ascent to an altitude of 4300-5400 meters significantly reduces the occurrence of symptoms of acute altitude sickness, including headache, fatigue, dyspnea, nausea, and vomiting, when compared with placebo (6230,87827). A standardized ginkgo leaf extract called EGb 761, 160 mg in two divided doses daily, was used in one of these studies (6230). However, a large-scale trial using a different ginkgo extract (GK501, Pharmaton Natural Health Products) 120 mg twice daily for 1-2 days before the climb from an altitude of 4280 meters to 4928 meters, shows that ginkgo extract has no effect on preventing altitude sickness (11766). Also, another small study suggests that taking ginkgo extract 120 mg twice daily for 3 days before an ascent does not reduce altitude sickness when compared with placebo (87827). The conflicting results may be due to differences in starting baseline altitudes before ascent, duration of the pre-treatment period, or the source of the ginkgo product.
• Asthma. Oral ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that a taking two capsules of a specific combination product (AKL1, AKL International Ltd.) containing ginkgo extract 130 mg/capsule, ginger 100 mg/capsule, and Picrorhiza 270 mg/capsule twice daily for 12 weeks does not improve lung function, respiratory symptoms, or quality of life when compared with placebo in adult patients with asthma (87786).
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral ginkgo is beneficial in ADHD. Details: One clinical study shows that taking a standardized ginkgo extract (Ginko T.D., Tolidaru Pharmaceuticals) 80-120 mg daily for 6 weeks is less effective than methylphenidate 20-30 mg daily in children aged 6-14 years with newly diagnosed ADHD. Only 8% of children taking ginkgo extract had at least a 40% improvement in a teacher/parent ADHD rating scale, compared with 64% in children taking methylphenidate (17112). Another clinical study in children aged 6-12 years with ADHD shows that taking the same standardized ginkgo extract 80-120 mg daily in combination with methylphenidate 20-40 mg daily for 6 weeks does not improve parent- or teacher-rated ADHD scores by a clinically meaningful amount when compared with methylphenidate alone (95669). However, one preliminary clinical study shows that taking a specific combination product (AD-fX, CV Technologies) containing ginkgo leaf extract 100 mg, in combination with American ginseng extract 400 mg, in two divided doses for 4 weeks might significantly improve ADHD symptoms such as anxiety, hyperactivity, and impulsivity in children aged 3-17 years (8235). Guidelines from The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce state that ginkgo extract at doses of 80-120 mg daily is not currently recommended for monotherapy or adjunctive use in children with ADHD due to mixed evidence (110318).
• Autism spectrum disorder. It is unclear if oral ginkgo is beneficial in children with autism. Details: A small clinical trial shows that taking a specific ginkgo extract (Ginko T.D., Tolidaru Pharmaceuticals) 80-120 mg daily for 10 weeks along with risperidone 1-3 mg daily does not improve symptoms of autism when compared with risperidone alone in children aged 4-12 years (89708).
• Bronchitis. Although there has been interest in using oral ginkgo for bronchitis, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Chronic fatigue syndrome (CFS). Oral ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in adults with CFS shows that taking ginkgo leaf 120-180 mg in combination with Cistanche tubulosa root 300-450 mg orally daily for 60 days improves fatigue scores by 16% to 19% when compared with placebo. Taking this combination also improved quality of life scores when compared with placebo (107361).
• Chronic kidney disease (CKD). There is limited evidence on the intravenous use of ginkgo leaf extract in adults with hypertensive nephropathy. It has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small meta-analysis in patients with hypertensive nephropathy shows that intravenous administration of 20-30 mL of ginkgo leaf extract and dipyridamole injection once daily for 3-4 weeks along with conventional antihypertensive therapy improves levels of 24-hour urinary total protein, serum creatinine, and blood urea nitrogen by 0.6 grams/dL, 33 mg/dL, and 7 mg/dL, respectively (106610). It is unclear if these effects are due to ginkgo, dipyridamole, or the combination.
• Chronic obstructive pulmonary disease (COPD). Oral ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research shows that taking two capsules of a specific combination product (AKL1, AKL International Ltd.) containing ginkgo extract, ginger, and Picrorhiza twice daily for 8 weeks does not improve respiratory symptoms when compared with placebo in patients with COPD (89702).
• Cocaine dependence. It is unclear if oral ginkgo is beneficial for maintenance of abstinence from cocaine. Details: A small clinical trial shows that taking a standardized ginkgo leaf extract called EGb 761 in a dose of 120 mg twice daily for 10 weeks does not help maintain abstinence from cocaine use when compared with placebo in cocaine-dependent patients (87723).
• Cognitive function. It is unclear if oral ginkgo is beneficial for cognitive function. Details: Clinical research in healthy adults shows that taking ginkgo leaf extract daily for up to 12 weeks might improve some measures of cognitive function, such as working and long term memory, attention based tasks, speed of information processing, executive function, immediate and delayed recall, and recognition (6214,6215,8236,8544,8585,8588,9759,16635,87788,87879,95668). Doses used in these studies include single doses of ginkgo extract 240-600 mg (6215,8236), a standardized ginkgo extract called EGb 761, 120-240 mg taken once daily or in 2-3 divided doses daily for 4-24 weeks (5717,6216,8585,8588,87879,95668), or another specific ginkgo extract called LI 1370 (Lichtwer Pharma), 120-300 mg daily in three divided doses for 2 days (6214). However, other clinical studies and one clinical review show no significant effect of ginkgo on gait ability, attention, memory, or executive function regardless of participant age, dose, or formulation used (87907,5718,8586,8587,8588,87907,95667). Due to the small number of study participants, significant differences in baseline cognitive function between groups, and variability in outcome measures, no definitive conclusions can be drawn. Larger scale studies are needed to determine the effect of ginkgo on cognitive function in healthy individuals. There is also conflicting evidence about the effect of ginkgo on cognitive function when taken in combination with other products. Some research suggests that taking ginkgo in combination with Panax ginseng or codonopsis enhances memory in healthy young or middle-aged adults, and the combinations might be more effective than the individual products (8591,9759,87758). These studies have used a specific combination product (Ginkoba M/E, Pharmaton SA) containing ginkgo extract 100-600 mg and Panax ginseng 60-360 mg, taken as a single dose or once daily for 12 weeks (8591,9759) or two capsules of a product containing ginkgo extract 40 mg/capsule and Codonopsis 75 mg/capsule daily (87758). However, other clinical research shows that taking ginkgo combined with Panax ginseng (Gincosan, Pharmaton Natural Health Products) or bacopa extract (Ginkgo Brahmi, Blackmore's Ltd.) for up to 12 weeks does not improve cognition when compared with placebo in healthy adults (87767,87748). Similarly, a moderate-sized clinical study in healthy adults aged 40-65 years shows that taking a supplement containing ginkgo leaf, bacopa, and B vitamins twice daily for 12 weeks does not improve memory or attention when compared with placebo (111334).
• Cognitive impairment. It is unclear if ginkgo is beneficial for cognitive impairment. Details: A clinical study of 500 patients with mild cognitive impairment that is abnormal for their age shows that taking a specific ginkgo standardized extract (EGb761, Tanakan) 40 mg three times daily for 24 months improves scores for cognitive decline, memory, activities of daily living, and depression when compared with baseline (105530). However, it is not clear if these improvements are clinically significant and the validity of the study is limited by the lack of a control group. Cognitive impairment is common side effect of electroconvulsive therapy (ECT). A small clinical study in patients aged 18-60 years with psychiatric disorders undergoing ECT in Iran shows that taking ginkgo (Vitarmonil Co., France) 200 mg after meals, starting 48 hours before initiation of ECT and continuing until the end of ECT sessions, modestly improves scores related to cognitive impairment and memory when compared with placebo (111338). However, it is unclear if these improvements are clinically significant.
• Colorectal cancer. Intravenous ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that adding intravenous ginkgo extract (EGb 761 ONC), 350 mg over 30 minutes on days 1-6 of every 3-week cycle to treatment with 5-fluorouracil 500 mg/m2 daily on days 2-6 of every 3-week cycle for 4 courses of treatment, might reduce disease progression in some patients with metastatic colorectal cancer (9872). However, since the study did not include a control group, it is unclear if the effects of treatment were greater than the effects of 5-fluorouracil alone.
• Cough. Although there has been interest in using oral ginkgo for cough, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Depression. It is unclear if oral ginkgo is beneficial in depression. Details: Preliminary clinical research in elderly patients shows that taking an unknown dose of a specific ginkgo extract (Harbin HaoBo Pharmaceutical Co., Ltd.) in conjunction with citalopram 20 mg daily for 12 weeks improves depression scores by 75% or more in an additional 3% of patients when compared with taking citalopram alone. Taking ginkgo extract with citalopram also produces a faster onset of action when compared to taking citalopram alone. However, it is not clear if these improvements are clinically significant (98811).
• Diabetes. Research on the use of oral ginkgo in type 2 diabetes is conflicting. Details: In patients with uncontrolled type 2 diabetes taking metformin, preliminary clinical research shows that taking ginkgo extract (EGb 761) 120 mg for 90 days reduces glycated hemoglobin (HbA1c) levels from an average of 8.6% at baseline to an average of 7.7%. Fasting serum glucose and insulin were also reduced, when compared with baseline, by approximately 20% and 28%, respectively (103574). However, a meta-analysis of 7 clinical studies shows that taking ginkgo is associated with an increase in HbA1c levels, with no effect on fasting serum glucose levels. The only beneficial effect identified in this analysis was an increase in high density lipoprotein (HDL) cholesterol levels (105529).
• Diabetic retinopathy. It is unclear if oral ginkgo is beneficial for this condition. Details: Preliminary clinical research shows that taking a specific ginkgo leaf extract called EGb 761 120 mg daily orally for 6 months improves measures of color vision when compared with placebo in patients with early diabetic retinopathy (6175).
• Dry eye. Ginkgo eye drops have only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A nonblinded clinical study in adults undergoing cataract surgery and receiving standard treatment shows that applying a specific, preservative-free eye drop (Trium Free; SOOFT) containing ginkgo extract 0.05% and hyaluronic acid 0.15%, three times daily, beginning the first day after surgery and continued for 4 weeks, reduces dry eye severity and symptoms when compared with standard treatment alone. After 4 weeks, 50% of patients in the standard treatment group reported dry eye symptoms, compared with 16% of patients using ginkgo (108609). The effects of ginkgo in patients with chronic dry eye or dry eye caused by other factors is unclear.
• Dyslexia. It is unclear if oral ginkgo is beneficial for dyslexia in children. Details: Preliminary clinical research shows that taking a standardized ginkgo leaf extract (EGb 761) 80 mg daily for an average of 34 days can help reduce dyslexia when compared to baseline in children aged 5-16 years (87790). The validity of this finding is limited by the lack of a comparator group.
• Fibromyalgia. Oral ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that taking tablets containing ginkgo extract (Bio-Biloba, Pharma Nord) 200 mg daily in conjunction with capsules containing coenzyme Q10 (Bio Quinone Q10, Pharma Nord) 200 mg daily orally for 84 days improves patient-reported quality of life, such as physical fitness levels, emotional feelings, social activities, overall health, and pain, when compared to baseline (17716). The validity of these findings is limited by the lack of a comparator group.
• Gastric cancer. It is unclear if oral ginkgo is beneficial in gastric cancer. Details: Preliminary clinical research shows that taking carbohydrates from the outer layer of ginkgo fruit 250 mg orally twice daily for 30 days may reduce tumor size in patients with gastric cancer when compared with pre-treatment (87742).
• Glaucoma. It is unclear if oral ginkgo is beneficial in glaucoma. Details: A small observational study has found that taking ginkgo leaf extract 80 mg twice daily for up to 12.3 years is associated with reduced progression of visual field damage in patients with normal tension glaucoma (87900). Furthermore, a small clinical study in patients with normal tension glaucoma shows that taking ginkgo leaf extract 40 mg three times daily for up 4 weeks might improve pre-existing damage and reduce the progression of damage to the visual field (10378). However, conflicting evidence exists. Another small study in patients with newly diagnosed normal tension glaucoma shows that taking a specific ginkgo extract (Ginaton, Dr. Willmar Schwabe Pharmaceuticals) 40 mg three times daily for 4 weeks does not improve damage or progression of glaucoma (89707). Reasons for the discrepancies may be due to the formulation of ginkgo leaf extract used or the severity of glaucoma at baseline.
• Hemorrhoids. Oral ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: One small clinical study shows that taking a combination of ginkgo extract, troxerutin, and heptaminol for one week may decrease some symptoms of hemorrhoids, including bleeding, pain, feelings of incomplete defecation, and discharge when compared to baseline (87751). The validity of these findings is limited by the lack of a comparator group. Additionally, it is unclear if these effects are due to ginkgo, other ingredients, or the combination.
• Hypercholesterolemia. Although there has been interest in using oral ginkgo for hypercholesterolemia, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Intestinal parasite infection. Although there has been interest in using oral ginkgo for intestinal parasite infection, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Lyme disease. Although there has been interest in using oral ginkgo for cognitive dysfunction associated with Lyme disease, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Migraine headache. Oral ginkgolide B, a constituent of ginkgo biloba extract, has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that ginkgolide B (BN52021), a constituent of ginkgo extract, along with coenzyme Q10, riboflavin, and magnesium, taken twice daily for 3 months, may help prevent migraines in school-aged children when compared to baseline (44181,87876). Also, a specific product (Migrasoll, Pharmaval Srl) containing ginkgolide B 60 mg, coenzyme Q10 11 mg, and vitamin B2 8.7 mg, taken twice daily for 4 months, may help prevent migraines in females when compared to baseline (44103). The validity of the findings from these studies is limited by the lack of a comparator group.
• Ovarian cancer. It is unclear if oral ginkgo is beneficial in preventing ovarian cancer. Details: Epidemiological evidence found that use of ginkgo extract for 6 months is associated with a decreased risk for developing ovarian cancer (14813).
• Pancreatic cancer. Intravenous ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that adding a specific intravenous ginkgo extract called EGb 761 ONC 350 mg on days 1-6 of every 3-week cycle to treatment with 5-fluorouracil 500 mg/m2 daily on days 2-6 of every 3-week cycle until disease progression might slow the progression of pancreatic cancer in some patients (87699). However, since the study did not include a control group, it is unclear if the effects of treatment were greater than the effects of 5-fluorouracil alone.
• Parkinson disease. It is unclear if oral ginkgo is beneficial for drug-induced Parkinsonism. Details: Preliminary clinical research in patients with psychiatric diagnoses treated with antipsychotic drugs shows that taking dried ginkgo extract, 80 mg three times daily orally for 3 months, reduces resting tremors, rigidity, bradykinesia, and the severity of motor symptoms when compared with placebo (112945).
• Peripheral arterial disease (PAD). It is unclear if oral ginkgo is beneficial in PAD. Details: Some small clinical studies show that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals and Ipsen) orally increases pain-free walking distance in patients with Fontaine's IIb peripheral arterial occlusive disease and intermittent claudication and might decrease overall peripheral vascular disease (PVD) event incidence, such as surgery or amputation, in elderly patients (3461,6211,6212,6213,17402). Significant benefit has been found with doses as low as 120-160 mg daily (6211). However, there is some evidence that a higher dose of 240 mg daily might be more beneficial in some patients (3461,6212). Although some research is positive, other research shows that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) 300 mg daily for 16 weeks does not significantly improve maximum treadmill walking time when compared with placebo in patients with PAD (16638). A reason for this discrepancy may be due to the duration of treatment. A meta-analysis of clinical research shows that taking ginkgo leaf extract does not improve maximum treadmill walking distance when compared with placebo in patients with Fontaine stage II PVD and intermittent claudication when administered for 6-8 weeks or 12-16 weeks, but does increase maximum treadmill walking distance by about 85 meters when administered for at least 24 weeks (89440).
• Pulmonary hypertension. It is unclear if intravenous ginkgo is beneficial in patients with pulmonary hypertension and cor pulmonale. Details: A meta-analysis of 28 small, low-quality clinical trials, including nearly 2500 Chinese patients with pulmonary hypertension and cor pulmonale, shows that intravenous administration of ginkgo leaf extract plus dipyridamole 15-40 mL daily for 1-4 weeks along with conventional therapy increases the total effective rate by 28% and improves various blood gas measures when compared with conventional therapy alone (102881). It is unclear if these effects are due to ginkgo, dipyridamole, or the combination. Large, high-quality clinical trials are needed to confirm these results.
• Quality of life. Some preliminary clinical studies suggest that oral ginkgo might improve quality of life in elderly individuals. Details: A large survey-based study shows that taking a standardized ginkgo leaf extract called LI 1370 (Lichtwer Pharma) 120 mg daily for 4-10 months may improve quality of life measures such as activities of daily living, mood, sleep, and alertness in elderly individuals when compared with control (87715,87760).
• Radiation exposure. It is unclear if intravenous ginkgo is beneficial in people who have been exposed to radiation. Details: Preliminary clinical research shows that taking a standardized ginkgo leaf extract called EGb 761 (Tanakan, Ipsen) 120 mg daily for 2 months might reduce clastogenic factors in the blood of patients who had previously been irradiated. The reduction in clastogenic factors was observed for at least 7 months after initiation of ginkgo in most patients (17719).
• Radiation dermatitis. Topical ginkgo has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research shows that applying a specific cream product (Radioskin 2, Herbalab di Perazza Massimiliano Company) containing ginkgo extract, Aloe vera, and metal esculetina, along with another specific cream product (Radioskin 1) containing alga atlantica and ethylbisiminomethylguaicolo manganese cloruro, may improve skin hydration and reduce skin toxicity associated with radiation therapy in patients with breast cancer (89727). The creams were applied topically 2-3 times daily at least 3 hours before and after radiation treatment from 15 days prior to radiation until one month after completion. It is unclear if these effects are due to ginkgo, other ingredients, or the combination.
• Raynaud syndrome. Evidence for the use of oral ginkgo for flare reduction is conflicting. Details: Some research shows that taking a standardized ginkgo extract (Seredrin, Health Perception Ltd.) 120 mg orally three times daily for 10 weeks can decrease the number of painful attacks per week in patients with Raynaud syndrome (11363). However, other research shows that ginkgo extract is no different than placebo in decreasing the number of attacks in these patients (87888). Also, another study shows that taking ginkgo extract 120 mg daily is less effective than nifedipine SR 30 mg daily orally in decreasing Raynaud syndrome flares (87818).
• Scabies. Although there has been interest in using topical ginkgo for scabies, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Seasonal affective disorder (SAD). It is unclear if oral ginkgo is beneficial for SAD. Details: One small clinical study shows that taking ginkgo leaf extract orally does not seem to prevent winter depression symptoms in patients with SAD when compared with placebo (8233).
• Sexual dysfunction. It is unclear if oral ginkgo is beneficial for sexual dysfunction in females. Details: Some clinical research shows that taking a ginkgo leaf extract 300 mg daily for 8 weeks does not significantly improve sexual function in females with sexual arousal disorder when compared with placebo (16640). However, other preliminary clinical research shows that taking a specific combination product (ArginMax for Women, Daily Wellness Company) containing ginkgo leaf extract, Panax ginseng root extract, damiana leaf extract, L-arginine, multivitamins, and minerals for 4 weeks can improve sexual satisfaction when compared with placebo in females who self-report sexual dysfunction (46933). It is unclear if these effects are due to ginkgo, other ingredients, or the combination.
• Venous thromboembolism (VTE). Although there has been interest in using oral ginkgo for thrombosis, there is insufficient reliable information about the clinical effects of ginkgo for this condition.
• Vitiligo. It is unclear if oral ginkgo is beneficial for reducing vitiligo progression. Details: Preliminary clinical research shows that taking a specific ginkgo extract (Ginkgo Plus, Seroyal) 120 mg in two divided doses daily for up to 6 months reduces the progression of vitiligo vulgaris and lesion size when compared to baseline (17718,87728). The validity of these findings is limited by the lack of a comparator group.
• Wound healing. Although there has been interest in using topical ginkgo for healing of skin sores or chilblains, there is insufficient reliable information about the clinical effects of ginkgo for these conditions. More evidence is needed to rate ginkgo for these uses.

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POSSIBLY EFFECTIVE

• Vitiligo. Taking picrorhiza orally for up to 1 year, in combination with oral and topical methoxsalen, seems to help treat vitiligo in adults and children (11493).

POSSIBLY INEFFECTIVE

• Asthma. Taking picrorhiza orally for up to 12 weeks does not seem to help asthma symptoms or improve measurements of lung function (11858).

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Chronic obstructive pulmonary disease (COPD). A small clinical study in patients with COPD and chronic cough shows that taking two capsules of a specific combination product (AKL1, AKL International Ltd.) containing picrorhiza ginkgo extract, and ginger twice daily for 8 weeks does not improve cough or other respiratory symptoms when compared with placebo (89702).
• Hepatitis. Preliminary clinical research suggests that picrorhiza, given orally for 2 weeks, might help acute viral hepatitis. It seems to improve symptoms such as anorexia, nausea, and malaise, as well as lower bilirubin and transaminase levels (11848). Picrorhiza has not been tested in patients with hepatitis B. More evidence is needed to rate picrorhiza for these uses.

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

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

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

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

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

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

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

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LIKELY SAFE ...when used orally and appropriately. Standardized ginkgo leaf extracts have been used safely in trials lasting for several weeks up to 6 years (1514,1515,3461,5717,5718,6211,6212,6213,6214,6215)(6216,6222,6223,6224,6225,6490,14383,14499,16634,16635)(16636,16637,17402,17716,17718,87794,87819,87826,87848,87864)(87888,87897,87901,87904,89701,89707,107359,107360). There have been some reports of arrhythmias associated with ginkgo leaf extract. However, it is not yet clear if ginkgo might cause arrhythmia (105253,105254). There is some concern about toxic and carcinogenic effects seen in animals exposed to a ginkgo leaf extract containing 31.2% flavonoids, 15.4% terpenoids, and 10.45 ppm ginkgolic acid, in doses of 100 to 2000 mg/kg five times per week for 2 years (18272). However, the clinical relevance of this data for humans, using typical doses, is unclear. The content of the extract used is not identical to that commonly used in supplement products, and the doses studied are much higher than those typically used by humans. A single dose of 50 mg/kg in rats is estimated to be equivalent to a single dose of about 240 mg in humans (18272).

POSSIBLY SAFE ...when used intravenously, short-term. A standardized ginkgo leaf extract called EGb 761 ONC has been safely administered intravenously for up to 14 days (9871,9872,107360,107452). A Chinese preparation containing ginkgo leaf extract and dipyridamole has been safely administered intravenously for up to 30 days (102881,102882). ...when applied topically, short-term. There was no dermal irritation during a 24-hour patch test using the leaf extract, and no sensitization with repeat applications (112946). When used topically in cosmetics, extracts of ginkgo leaves are reported to be safe, but there is insufficient data to determine the safety of nut and root extracts, and isolated biflavones and terpenoids (112946).

POSSIBLY UNSAFE ...when the roasted seed or crude ginkgo plant is used orally. Consuming more than 10 roasted seeds per day can cause difficulty breathing, weak pulse, seizures, loss of consciousness, and shock (8231,8232). Crude ginkgo plant parts can exceed concentrations of 5 ppm of the toxic ginkgolic acid constituents and can cause severe allergic reactions (5714).

LIKELY UNSAFE ...when the fresh ginkgo seed is used orally. Fresh seeds are toxic and potentially deadly (11296).

PREGNANCY: POSSIBLY UNSAFE
when used orally. There is concern that ginkgo might have labor-inducing and hormonal effects. There is also concern that the antiplatelet effects of ginkgo could prolong bleeding time if taken around the time of labor and delivery (15052). Theoretically, ginkgo might adversely affect pregnancy outcome; avoid using during pregnancy.

LACTATION:
Insufficient reliable information available; avoid using.

CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term (87790,89708). A specific ginkgo dried extract (Ginko T.D., Tolidaru Pharmaceuticals), has been safely used in doses of 80-120 mg daily for 6 weeks in children aged 6-14 years (17112,95669). Another specific combination product containing ginkgo leaf extract and American ginseng extract (AD-FX, CV Technologies, Canada) has also been safely used in children aged 3-17 years for up to 4 weeks (8235).

CHILDREN: LIKELY UNSAFE
when ginkgo seed is used orally. The fresh seeds have caused seizures and death in children (8231,11296).

(Read more about GINKGO)

POSSIBLY SAFE ...when used orally and appropriately. Picrorhiza seems to be safe when used for up to 1 year (11493,11848,11858).

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

(Read more about PICRORHIZA)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

(Read more about GINGER)

ALPRAZOLAM (Xanax) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, ginkgo might decrease the levels and clinical effects of alprazolam.  Details In clinical research, ginkgo extract (Ginkgold) 120 mg twice daily seems to decrease alprazolam levels by about 17%. However, ginkgo does not appear to decrease the elimination half-life of alprazolam. This suggests that ginkgo is more likely to decrease absorption of alprazolam rather than induce hepatic metabolism of alprazolam (11029).

ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = A Ginkgo has been shown to increase the risk of bleeding in some people when taken with warfarin. Theoretically, ginkgo might increase the risk of bleeding if used with other anticoagulant or antiplatelet drugs.  Details Several pharmacodynamic studies suggest that ginkgo inhibits platelet aggregation. It is thought that the ginkgo constituent, ginkgolide B, displaces platelet-activating factor (PAF) from its binding sites, decreasing blood coagulation (6048,9760). Several case reports have documented serious bleeding events in patients taking ginkgo (244,578,579,8581,13002,13135,13179,13194,14456,87868). However, population and clinical studies have produced mixed results. Some evidence shows that short-term use of ginkgo leaf does not significantly reduce platelet aggregation and blood clotting (87732). A study in healthy males who took a specific ginkgo leaf extract (EGb 761) 160 mg twice daily for 7 days found no change in prothrombin time (12114). An analysis of a large medical record database suggests that ginkgo increases the risk of a bleeding adverse event by 38% when taken concurrently with warfarin (91326). It has been suggested that ginkgo has to be taken for at least 2-3 weeks to have a significant effect on platelet aggregation (14811). However, a meta-analysis of 18 studies using standardized ginkgo extracts, 80-480 mg daily for up to 32 weeks, did not find a significant effect on platelet aggregation, fibrinogen concentration, or PT/aPTT (17179). In addition, a single dose of ginkgo plus clopidogrel (14811) or ticlopidine does not seem to significantly increase bleeding time or platelet aggregation (17111,87846). Also, taking ginkgo leaf extract daily for 8 days in conjunction with rivaroxaban does not affect anti-factor Xa activity; however, this study did not evaluate bleeding time (109526).

ANTICONVULSANTS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might reduce the effectiveness of anticonvulsants.  Details Ginkgo seeds contain ginkgotoxin. Large amounts of ginkgotoxin can cause neurotoxicity and seizure. Ginkgotoxin is present in much larger amounts in ginkgo seeds than leaves (8232). Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity (11296). However, there are anecdotal reports of seizure occurring after use of ginkgo leaf both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090).

ANTIDIABETES DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, taking ginkgo with antidiabetes drugs might alter the response to antidiabetes drugs.  Details Ginkgo leaf extract seems to alter insulin secretion and metabolism, and might affect blood glucose levels in people with type 2 diabetes (5719,14448,103574). The effect of ginkgo seems to differ depending on the insulin and treatment status of the patient. In diet-controlled diabetes patients with hyperinsulinemia, taking ginkgo does not seem to significantly affect insulin or blood glucose levels. In patients with hyperinsulinemia who are treated with oral hypoglycemic agents, taking ginkgo seems to decrease insulin levels and increase blood glucose following an oral glucose tolerance test. Researchers speculate that this could be due to ginkgo-enhanced hepatic metabolism of insulin. In patients with pancreatic exhaustion, taking ginkgo seems to stimulate pancreatic beta-cells, resulting in increased insulin and C-peptide levels, but with no significant change in blood glucose levels in response to an oral glucose tolerance test (14448).

ATORVASTATIN (Lipitor) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, ginkgo might decrease the levels and clinical effects of atorvastatin.  Details In humans, intake of ginkgo extract appears to increase atorvastatin clearance, reducing the area under the curve of atorvastatin by 10% to 14% and the maximum concentration by 29%. However, this interaction does not appear to affect cholesterol synthesis and absorption (89706). Further, a model in rats with hyperlipidemia suggests that administering ginkgo extract does not impact blood levels of atorvastatin and leads to lower total cholesterol, low-density lipoprotein cholesterol, and triglycerides when compared with rats given atorvastatin alone (111331).

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, ginkgo might increase levels of drugs metabolized by CYP1A2.  Details Laboratory research suggests that ginkgo leaf extract can mildly inhibit CYP1A2 enzymes (1303,6423,6450). However, clinical research suggests ginkgo might not affect CYP1A2 (10847). Until more is known, use ginkgo cautiously in patients taking drugs metabolized by these enzymes.

CYTOCHROME P450 2C19 (CYP2C19) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Probable •  Level of Evidence = B Theoretically, ginkgo might decrease levels of drugs metabolized by CYP2C19.  Details Some clinical research shows that a specific ginkgo leaf extract (Remembrance, Herbs Product LTD) 140 mg twice daily can induce CYP2C19 enzymes and potentially decrease levels of drugs metabolized by these enzymes (13108). However, other clinical research shows that taking ginkgo 120 mg twice daily for 12 days has no effect on levels of drugs metabolized by CYP2C19 (87824).

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might increase levels of drugs metabolized by CYP2C9.  Details In vitro, a specific standardized extract of ginkgo leaf (EGb 761) inhibits CYP2C9 activity (11026,12061,14337). The terpenoid (ginkgolides) and flavonoid (quercetin, kaempferol, etc.) constituents seem to be responsible for this effect. Most ginkgo extracts contain some amount of these constituents. Therefore, other ginkgo leaf extracts might also inhibit the CYP2C9 enzyme. However, clinical research suggests that ginkgo might not have a significant effect on CYP2C9 in humans. Ginkgo does not seem to significantly affect the pharmacokinetics of CYP2C9 substrates diclofenac or tolbutamide.

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = B Theoretically, ginkgo might decrease levels of drugs metabolized by CYP3A4.  Details There is conflicting evidence about whether ginkgo induces or inhibits CYP3A4 (1303,6423,6450,11026,87800,87805,111330). Ginkgo does not appear to affect hepatic CYP3A4 (11029). However, it is not known if ginkgo affects intestinal CYP3A4. Preliminary clinical research suggests that taking ginkgo does not significantly affect levels of donepezil, lopinavir, or ritonavir, which are all CYP3A4 substrates (11027,87800,93578). Other clinical research also suggests ginkgo does not significantly affect CYP3A4 activity (10847). However, there are two case reports of decreased efavirenz concentrations and increased viral load in patients taking ginkgo. It is suspected that terpenoids from the ginkgo extract reduced drug levels by inducing cytochrome P450 3A4 (CYP3A4) (16821,25464).

EFAVIRENZ (Sustiva) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might decrease the levels and clinical effects of efavirenz.  Details There are two case reports of decreased efavirenz concentrations and increased viral load in patients taking ginkgo. In one case, an HIV-positive male experienced over a 50% decrease in efavirenz levels over the course of 14 months while taking ginkgo extract. HIV-1 RNA copies also increased substantially, from less than 50 to more than 1500. It is suspected that terpenoids from the ginkgo extract reduced drug levels by inducing cytochrome P450 3A4 (CYP3A4) (16821). In another case report, a patient stable on antiviral therapy including efavirenz for 10 years, had an increase in viral load from <50 copies/mL to 1350 copies/mL after 2 months of taking a combination of supplements including ginkgo. After stopping ginkgo, the viral load was again controlled with the same antiviral therapy regimen (25464).

IBUPROFEN (Advil, others) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might increase the risk of bleeding when used with ibuprofen.  Details Ginkgo might have antiplatelet effects and has been associated with several case reports of spontaneous bleeding. In one case, a 71-year-old male had taken a specific ginkgo extract (Gingium, Biocur) 40 mg twice daily for 2.5 years. About 4 weeks after starting ibuprofen 600 mg daily he experienced a fatal intracerebral hemorrhage (13179). However, the antiplatelet effects of ginkgo have been questioned. A meta-analysis and other studies have not found a significant antiplatelet effect with standardized ginkgo extracts, 80 mg to 480 mg taken daily for up to 32 weeks (17179).

NIFEDIPINE (Procardia) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, taking ginkgo with oral, but not intravenous, nifedipine might increase levels and adverse effects of nifedipine.  Details Animal research and some clinical evidence suggests that taking ginkgo leaf extract orally in combination with oral nifedipine might increase nifedipine levels and cause increased side effects, such as headaches, dizziness, and hot flushes (87764,87765). However, taking ginkgo orally does not seem to affect the pharmacokinetics of intravenous nifedipine (87765).

OMEPRAZOLE (Prilosec) Interaction Rating = Minor Be watchful with this combination. Severity = Mild •  Occurrence = Possible •  Level of Evidence = B Theoretically, taking ginkgo with omeprazole might decrease the levels and clinical effects of omeprazole.  Details Clinical research shows that a specific ginkgo leaf extract (Remembrance, Herbs Product LTD) 140 mg twice daily can induce cytochrome P450 (CYP) 2C19 enzymes and decrease levels of omeprazole by about 27% to 42% (13108).

P-GLYCOPROTEIN SUBSTRATES Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Theoretically, taking ginkgo with P-glycoprotein substrates might increase the levels and adverse effects of these substrates.  Details A small clinical study in healthy volunteers shows that using ginkgo leaf extract 120 mg orally three times daily for 14 days can increase levels of the P-glycoprotein substrate, talinolol, by 36% in healthy male individuals. However, single doses of ginkgo do not have the same effect (87830).

RISPERIDONE (Risperdal) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking ginkgo with risperidone might increase the levels and adverse effects of risperidone.  Details A single case of priapism has been reported for a 26-year-old male with schizophrenia who used risperidone 3 mg daily along with ginkgo extract 160 mg daily (87796). Risperidone is metabolized by cytochrome P450 (CYP) 2D6 and CYP3A4. CYP3A4 activity might be affected by ginkgo. Theoretically, ginkgo may inhibit the metabolism of risperidone and increase the risk of adverse effects.

ROSIGLITAZONE (Avandia) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might decrease the levels and clinical effects of rosiglitazone.  Details Animal research shows that ginkgo leaf extract orally 100 or 200 mg/kg daily for 10 days alters the pharmacodynamics of rosiglitazone in a dose-dependent manner. The 100 mg/kg and 200 mg/kg doses reduce the area under the concentration time curve (AUC) of rosiglitazone by 39% and 52%, respectively, and the half-life by 28% and 39%, respectively. It is hypothesized that these changes may be due to induction of cytochrome P450 2C8 by ginkgo (109525).

SEIZURE THRESHOLD LOWERING DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, taking ginkgo with drugs that lower the seizure threshold might increase the risk for convulsions.  Details Ginkgo seeds contain ginkgotoxin. Large amounts of ginkgotoxin can cause neurotoxicity and seizure. Ginkgotoxin is present in much larger amounts in ginkgo seeds than leaves (8232). Ginkgo leaf extract contains trace amounts of ginkgotoxin. The amount of ginkgotoxin in ginkgo leaf and leaf extract seems unlikely to cause toxicity (11296). However, there are anecdotal reports of seizure occurring after use of ginkgo leaf both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090,14281).

SIMVASTATIN (Zocor) Interaction Rating = Moderate Be cautious with this combination. Severity = Mild •  Occurrence = Probable •  Level of Evidence = B Theoretically, ginkgo might decrease the levels and clinical effects of simvastatin.  Details Clinical research shows that taking ginkgo extract can reduce the area under the curve and maximum concentration of simvastatin by 32% to 39%. However, ginkgo extract does not seem to affect the cholesterol-lowering ability of simvastatin (89704).

SOFOSBUVIR (Sovaldi) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might increase the levels and clinical effects of sofosbuvir.  Details Animal research in rats shows that giving a ginkgo extract 25 mg/kg orally daily for 14 days increases the area under the concentration time curve (AUC) after a single sofosbuvir dose of 40 mg/kg by 11%, increases the half-life by 60%, and increases the plasma concentration at 4 hours by 38%. This interaction appears to be related to the inhibition of intestinal P-glycoprotein by ginkgo (109524).

TACROLIMUS (Prograf) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might increase the blood levels of tacrolimus.  Details In vitro evidence suggests that certain biflavonoids in ginkgo leaves (i.e. amentoflavone, ginkgetin, bilobetin) may inhibit the metabolism of tacrolimus by up to 50%. This interaction appears to be time-dependent and due to inhibition of cytochrome P450 (CYP) 3A4 by these bioflavonoids. In rats given tacrolimus 1 mg/kg orally, amentoflavone was shown to increase the area under the concentration time curve (AUC) of tacrolimus by 3.8-fold (111330).

TALINOLOL Interaction Rating = Major Do not take this combination. Severity = High •  Occurrence = Probable •  Level of Evidence = B Taking ginkgo with talinolol seems to increase blood levels of talinolol.  Details There is some evidence that using ginkgo leaf extract 120 mg orally three times daily for 14 days can increase levels of talinolol by 36% in healthy male individuals. However, single doses of ginkgo do not seem to affect talinolol pharmacokinetics (87830).

TRAZODONE (Desyrel) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, ginkgo might increase the levels and clinical effects of trazodone.  Details In a case report, an Alzheimer patient taking trazodone 20 mg twice daily and ginkgo leaf extract 80 mg twice daily for four doses became comatose. The coma was reversed by administration of flumazenil (Romazicon). Coma might have been induced by excessive GABA-ergic activity. Ginkgo flavonoids are thought to have GABA-ergic activity and act directly on benzodiazepine receptors. Ginkgo might also increase metabolism of trazodone to active GABA-ergic metabolites, possibly by inducing cytochrome P450 3A4 (CYP3A4) metabolism (6423).

WARFARIN (Coumadin) Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = B Ginkgo has been shown to increase the risk of bleeding in some people when taken with warfarin.  Details Several pharmacodynamic studies suggest that ginkgo inhibits platelet aggregation. It is thought that the ginkgo constituent, ginkgolide B, displaces platelet-activating factor (PAF) from its binding sites, decreasing blood coagulation (6048,9760). Several case reports have documented serious bleeding events in patients taking ginkgo (244,576,578,579,8581,13002,13135,13179,13194,14456,87868). Information from a medical database suggests that when taken concurrently with warfarin, ginkgo increases the risk of a bleeding adverse event by 38% (91326). There is also some evidence that ginkgo leaf extract can inhibit cytochrome P450 2C9, an enzyme that metabolizes warfarin. This could result in increased warfarin levels (12061). However, population and clinical research has produced mixed results. Clinical research in healthy people suggests that ginkgo has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin (12881,15176,87727,87889). A meta-analysis of 18 studies using standardized ginkgo extracts, 80 mg to 480 mg daily for up to 32 weeks, did not find a significant effect on platelet aggregation, fibrinogen concentration, or PT/aPTT (17179). There is also some preliminary clinical research that suggests ginkgo might not significantly increase the effects of warfarin in patients that have a stable INR (11905).

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(Read more about PICRORHIZA)

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

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

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

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

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

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

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

(Read more about GINGER)

General ...Orally, ginkgo leaf extract is generally well tolerated when used for up to 6 years. However, the seed and crude plant contain toxic constituents and should be avoided.
Intravenously, ginkgo leaf extract seems to be well tolerated when used for up to 30 days.
Topically, no adverse effects have been reported with ginkgo as a single ingredient. However, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Orally: Dizziness, gastrointestinal symptoms, headache.
Serious Adverse Effects (Rare):
Orally: Arrhythmia, bleeding, Stevens-Johnson syndrome.

Cardiovascular ...Cardiac arrhythmias suspected to be related to ginkgo have been reported. Internationally, there are at least 162 reports from 18 countries, with 34% of cases considered serious, involving five deaths and four life-threatening events. Additionally, a report from Canada found that 10 out of 15 cases of arrhythmia were considered serious. Ginkgo was the only suspect ingredient in 57% of all international reports, with symptoms generally presenting within days of initiation. The most common symptoms included palpitations, tachycardia, bradycardia, syncope, and loss of consciousness. Most cases were reported to be related to oral use of ginkgo leaf products; however, some cases were associated with oral use of the seed, and others with intravenous or intramuscular use of the leaf. Documented discontinuation of ginkgo led to recovery in approximately 84% of cases where ginkgo was the sole suspect. Despite these findings, ginkgo cannot be confirmed as the causal agent. It is possible that these reports are confounded by underlying co-morbidities. Of the reported cases, the main reason for ginkgo use was tinnitus, a symptom commonly associated with pre-existing arrhythmias (105253,105254). Despite this large number of reports, only three cases of cardiac arrhythmia have been published in the literature (105253,105254). In one case, frequent nocturnal episodes of paroxysmal atrial fibrillation were reported for a 35-year-old female taking ginkgo extract 240 mg daily orally for 2 months. Arrythmias ceased following discontinuation of ginkgo (87884).
In one clinical trial, the rate of ischemic stroke and transient ischemic attacks was significantly higher in patients taking ginkgo extract orally when compared with placebo (16635). It is unclear if these events were due to ginkgo, other factors, or a combination.

Dermatologic ...Topically, ginkgo fruit pulp can cause contact dermatitis, with intense itching, edema, papules, and pustules which take 7-10 days to resolve after stopping contact (112946).

Gastrointestinal ...Orally, ginkgo extract may cause mild gastrointestinal discomfort or pain (3965,8543,17112,87818,87858), nausea and vomiting (8543,17112,87728,87844,87858), diarrhea (87844), dry mouth (17112), and constipation (5719,87787). However, post-market surveillance suggests that the incidence of these events is relatively low, occurring in less than 2% of patients (88007).
Fresh ginkgo seeds can cause stomach ache, nausea, vomiting, or diarrhea. Ingesting roasted seeds in amounts larger than the normal food amounts of 8-10 seeds per day, or long-term, can also cause these same adverse reactions (8231,8232).

Genitourinary ...Orally, ginkgo extract has been reported to cause blood in the urine in one patient (87858).

Hematologic ...Spontaneous bleeding is one of the most concerning potential side effects associated with ginkgo. There are several published case reports linking ginkgo to episodes of minor to severe bleeding; however, not all case reports clearly establish ginkgo as the cause of bleeding. In most cases, other bleeding risk factors were also present including taking other medications or natural medicines, old age, liver cirrhosis, recent surgery, and other conditions. In most cases, bleeding occurred after several weeks or months of taking ginkgo (13135). Large-scale clinical trials and a meta-analysis evaluating standardized ginkgo leaf extracts show that the incidence of bleeding in patients taking ginkgo is not significantly higher than in those taking placebo (16634,16635,17179,17402).
There are several case reports of intracerebral bleeding. Some of these cases resulted in permanent neurological damage and one case resulted in death (244,578,8581,13135,13179,14456,87868,87977).
There are at least 4 cases of ocular bleeding including spontaneous hyphema (bleeding from the iris into the anterior part of the eye) and retrobulbar hemorrhage associated with ginkgo use (579,10450,13135).
There are also cases of surgical and post-surgical complications in patients using ginkgo. Retrobulbar hemorrhage (bleeding behind the eye) during cataract surgery has been associated with ginkgo use (10450). Excessive postoperative bleeding requiring transfusion has also occurred following laparoscopic surgery in a patient who had been taking ginkgo leaf extract (887). There have also been two cases of excessive bleeding during surgery and post-surgical hematoma in patients undergoing rhytidoplasty and blepharoplasty (13002). In another case, an elderly patient taking ginkgo experienced excessive postoperative bleeding following total hip arthroplasty (13194). In another case, use of ginkgo following liver transplantation surgery was associated with subphrenic hematoma requiring evacuation by laparotomy. The patient also subsequently experienced vitreous hemorrhage (14315). In another case, an elderly patient who had taken ginkgo chronically experienced excessive post-operative bleeding following an ambulatory surgical procedure (14453).
In another case, an elderly man experienced nose bleeds and ecchymosis following use of ginkgo. One case of diffuse alveolar hemorrhage in a female taking ginkgo and ginseng for over one year has been reported (95670). These instances of bleeding stopped when ginkgo was discontinued, and recurred when the patient started taking ginkgo again (13135).
Persistent bleeding has also occurred following dental surgery (87862) and laparoscopic cholecystectomy (88000). Nosebleed has also been reported as an adverse effect in a clinical trial (87813).

Immunologic ...Orally, ginkgo leaf extract can cause allergic skin reactions in some patients (14449,15578,112946). In one case, a patient developed acute generalized exanthematous pustulosis 48 hours after taking a single-ingredient ginkgo product. The rash resolved within 10 days after discontinuing ginkgo (14449). In another case, progressive erythema of the face, neck, trunk, and extremities occurred after two 60 mg oral doses of ginkgo extract (112946). There is also a case of Stevens-Johnson syndrome following a second administration of a preparation containing ginkgo leaf extract, choline, vitamin B6, and vitamin B12 (208). In another case, systemic edema and severe arthralgia was reported after contact with a ginkgo tree nut and manifested as multifocal lymphadenopathy associated with an allergic reaction on PET/CT scan imaging (95672).

Musculoskeletal ...Edema has been reported for three patients treated with ginkgo extract 40 mg orally three times daily (87818).

Neurologic/CNS ...Orally, ginkgo extract may cause headache (6220,8543,87818), dizziness (5719,87818), increased desire to sleep (87839), and sedation (10893) in some patients. In addition, although ginkgo leaf and ginkgo leaf extract contain only small amounts of ginkgotoxin, there are anecdotal reports of seizure occurring after use of ginkgo leaf preparations both in patients without a history of seizure disorder and in those with previously well-controlled epilepsy (7030,7090,11296,14281).

Ocular/Otic ...Orally, ginkgo extract may cause tinnitus is some patients, although the incidence is rare (8543).
Topically, eye drops containing ginkgo extract and hyaluronic acid may cause stinging sensations in some people (87829).

Psychiatric ...Orally, ginkgo has been associated with a single case of mood dysregulation. A 50-year-old female with schizophrenia developed irritability, difficulty controlling anger, and agitation after one week of taking ginkgo 80 mg twice daily. The mood changes resolved within 2-3 days of discontinuation. When ginkgo was re-trialed at a later date, the same symptoms reappeared, and again dissipated after discontinuation of the ginkgo product. The relationship between ginkgo and mood dysregulation was considered to be "probable" based on the Naranjo adverse drug reaction probability scale (96763); however, the exact mechanism by which ginkgo may have affected mood regulation is unknown.

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General ...Orally, picrorhiza may cause vomiting, rash, anorexia, diarrhea, itching, and giddiness (11858).

Dermatologic ...Orally, picrorhiza may cause rash and itching (11858).

Gastrointestinal ...Orally, picrorhiza may cause vomiting, anorexia, and diarrhea (11858).

Neurologic/CNS ...Orally, picrorhiza may cause giddiness (11858).

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