- What other names is Ginkgo known by?
- What is Ginkgo?
- Is Ginkgo effective?
- How does Ginkgo work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Ginkgo.
Ginkgo Safety and Side Effects
Ginkgo is safe for most people when used appropriately. It can cause some minor side effects such as stomach upset, headache, dizziness, constipation, forceful heartbeat, and allergic skin reactions.
There is some concern that ginkgo might increase the risk of bruising and bleeding. Ginkgo thins the blood and decreases its ability to form clots. A few people taking ginkgo have had bleeding into the eye and into the brain, and excessive bleeding following surgery.
Some research suggests that a specific combination of ginkgo leaf extract plus American ginseng might be safe in children when used short-term.
Ginkgo seeds might not be safe. Long-term use or use of medicinal amounts can cause serious side effects including stomachache, nausea, diarrhea, vomiting, restlessness, difficulty breathing, weak pulse, shock, seizures, loss of consciousness, and death.
Do not take ginkgo if..
Ginkgo leaf is often taken by mouth for memory disorders including Alzheimer's disease. It is also used for conditions that seem to be due to reduced blood flow in the brain, especially in older people. These conditions include memory loss, headache, ringing in the ears, vertigo, dizziness, difficulty concentrating, mood disturbances, and hearing disorders. Some people use it for other problems related to poor blood flow in the body, including leg pain when walking (claudication), and Raynaud's syndrome (a painful response to cold, especially in the fingers and toes).
Ginkgo leaf is also used for thinking disorders related to Lyme disease, chemotherapy, and depression.
Some people use ginkgo to treat sexual performance problems. It is sometimes used to reverse the sexual performance problems that can accompany taking certain antidepressants called SSRIs.
Ginkgo been used for eye problems including glaucoma, diabetic eye disease, and age-related macular degeneration (AMD), as well as attention deficit-hyperactivity disorder (ADHD), autism, heart disease and heart complications, high cholesterol, premenstrual syndrome (PMS), and bloody diarrhea. Ginkgo leaf is also taken by mouth for chronic fatigue syndrome (CFS), schizophrenia, and to prevent winter depression, preventing mountain sickness and aging, controlling stomach acid, improving liver and gallbladder function, and controlling blood pressure. It is also taken by mouth to treat asthma, allergies, bronchitis, and for disorders of the central nervous system.
The list of other uses of ginkgo is very long. This may be because this herb has been around for so long. Ginkgo biloba is one of the longest living tree species in the world. Ginkgo trees can live as long as a thousand years. Using ginkgo for asthma and bronchitis was described in 2600 BC.
In manufacturing, ginkgo leaf extract is used in cosmetics. In foods, roasted ginkgo seed, which has the pulp removed, is an edible delicacy in Japan and China.
Ginkgo might also help people who experience leg pain when they walk due to poor bloodflow. Ginkgo seems to be able to help people with this condition walk farther before the pain starts. It might also help people with balance problems, ease some of the symptoms of premenstrual syndrome (PMS) (especially breast tenderness), improve distance vision in people with macular degeneration, improve color vision in people with diabetes, and reverse the sexual side effects of certain medications for depression (such as Prozac, Paxil, Zoloft, etc.).
There isn't enough information to know if ginkgo leaf is effective for the other conditions people use it for, including: attention deficit-hyperactivity disorder (ADHD), blood clots, heart disease, high cholesterol, "hardening" of the arteries, depression, mountain sickness, and others.
Possibly Effective for...
- Anxiety. Research shows that taking a specific ginkgo extract (EGb 761, Dr. Willmar Schwabe Pharmaceuticals) for 4 weeks can reduce symptoms of anxiety.
- Mental function. Although some conflicting evidence exists, most research suggests that ginkgo can slightly improve memory, speed of thinking, and attention in healthy adults. Doses of 120-240 mg per day seem to be as effective as or more effective than higher doses up to 600 mg per day. Some research has investigated the effects of ginkgo when used with other supplements. Some evidence suggests that taking ginkgo in combination with Panax ginseng or codonopsis can improve memory better than the individual ingredients alone. However, a specific combination of ginkgo and Panax ginseng (Gincosan, Pharmaton Natural Health Products) does not seem to improve mood or thinking in postmenopausal women. Also, taking a specific product containing ginkgo and brahmi (Blackmores Ginkgo Brahmi) does not seem to improve memory or problem solving in healthy adults.
- Dementia. Some evidence shows that taking ginkgo leaf extract by mouth modestly improves symptoms of Alzheimer's, vascular, or mixed dementias. However, there are concerns that findings from many of the early ginkgo studies may not be reliable. Although most clinical trials show ginkgo helps for symptoms of Alzheimer's disease and other dementias, there are some conflicting findings, suggesting it may be hard to determine which people might benefit.
Early research shows that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) daily for 22-24 weeks seems to be as effective as the drug donepezil (Aricept) for treating mild to moderate Alzheimer's disease. But, other research suggests that ginkgo leaf extract might be less effective than the conventional drugs donepezil (Aricept) and tacrine (Cognex).
While ginkgo may help treat various types of dementia, ginkgo does not appear to help prevent dementia from developing.
- Vision problems in people with diabetes. There is some evidence that taking ginkgo leaf extract by mouth can improve color vision in people with retinal damage caused by diabetes.
- Vision loss (glaucoma). Taking ginkgo leaf extract by mouth for up to 12.3 years seems to improve pre-existing damage to the visual field in some people with normal tension glaucoma. However, conflicting research shows that ginkgo does not prevent glaucoma progression when taken for only 4 weeks.
- Leg pain when walking due to poor blood flow (peripheral vascular disease). Some evidence shows that taking ginkgo leaf extract increases the distance people with poor blood circulation in their legs can walk without pain. Taking ginkgo might also reduce the chance of requiring surgery. However, people with this condition may need to take ginkgo for at least 24 weeks before they see improvement.
- Premenstrual syndrome (PMS). Taking ginkgo leaf extract by mouth seems to relieve breast tenderness and other symptoms associated with PMS when started during the 16th day of the menstrual cycle and continued until the 5th day of the following cycle.
- Schizophrenia. Research shows that taking ginkgo daily in addition to conventional antipsychotic medications can reduce symptoms of schizophrenia. It may also reduce adverse effects associated with the antipsychotic medication, haloperidol.
- A movement disorder called tardive dyskinesia. Tardive dyskinesia is a movement disorder that is caused by certain antipsychotic drugs. Research shows that taking a specific ginkgo extract (EGb 761, Yi Kang Ning, Yang Zi Jiang Pharmaceuticals Ltd., Jiangsu, China) can reduce the severity of tardive dyskinesia symptoms in people with schizophrenia who are taking antipsychotic drugs.
- Vertigo and dizziness. Taking ginkgo leaf extract by mouth seems to improve symptoms of dizziness and balance disorders.
Possibly Ineffective for...
- Age-related memory loss. Some research suggests that ginkgo leaf extract might slightly improve memory and mental function in people with age-related memory problems. But most evidence shows that taking ginkgo leaf extract by mouth does not improve memory or attention in older people with normal mental function, in those with mild mental problems, or in those with dementia and age-related memory loss. Ginkgo also does not seem to prevent age-related memory loss from developing.
- Sexual dysfunction caused by antidepressant drugs. Although some early research suggests that taking ginkgo leaf extract by mouth might improve sexual problems caused by antidepressant drugs, more recent research suggests it is probably not effective.
- Mental problems caused by chemotherapy. Research shows that taking a specific ginkgo leaf extract called EGb 761 (Dr. Willmar Schwabe Pharmaceuticals) twice daily starting before the second cycle of chemotherapy and continuing until one month after chemotherapy treatment ends does not prevent mental problems caused by the chemotherapy in people being treated for breast cancer.
- High blood pressure. Research shows that taking a specific ginkgo leaf extract (EGb 761) by mouth for up to 6 years does not reduce blood pressure in older people with high blood pressure.
- Multiple sclerosis. Taking ginkgo leaf extract or ginkgolide B, a specific chemical found in ginkgo extract, does not improve mental function or disability in people with multiple sclerosis.
- Seasonal depression (seasonal affective disorder). Taking ginkgo leaf extract by mouth does not seem to prevent winter depression symptoms in people with seasonal depression.
- Ringing in the ears (tinnitus). Taking ginkgo leaf extract by mouth does not seem to improve ringing in the ears.
Likely Ineffective for...
- Heart disease. Taking a specific ginkgo extract (EGb 761, Dr. Willmar Schwabe Pharmaceuticals) does not reduce the chance of having a heart attack, chest pain, or stroke in elderly people.
Insufficient Evidence to Rate Effectiveness for...
- Age-related vison loss (age-related macular degeneration). There is some early evidence that ginkgo leaf extract might improve symptoms and distance vision in people with age-related vision loss.
- Hayfever (allergic rhinitis). Early research shows that applying specific eye drops (Trium, SOOFT) that contain ginkgo extract and hylauronic acid three times daily for one month can reduce eye redness, swelling and discharge in people with swollen eyes due to seasonal allergies.
- Altitude sickness. Research on the effects of ginkgo leaf extract on altitude sickness is inconsistent. Some research suggests that taking ginkgo leaf extract can reduce altitude sickness symptoms when taken 4 days before climbing. However, other research shows that using a specific ginkgo extract (GK501, Pharmaton Natural Health Products) for 1-2 days before climbing does not prevent altitude sickness.
- Asthma. Research shows that taking two capsules of a specific product containing ginkgo extract, ginger, and Picrorhiza kurroa (AKL1, AKL International Ltd) twice daily for 12 weeks does not improve lung function or asthma symptoms in adults with asthma.
- Attention deficit-hyperactivity disorder (ADHD). There is early evidence that a specific combination product (AD-fX, CV Technologies, Canada) containing ginkgo leaf extract, in combination with American ginseng (Panax quinquefolius), might help improve ADHD symptoms such as anxiety, hyperactivity, and impulsiveness in 3 to 17 year-old children. However, other research shows that taking ginkgo extract (Ginko T.D., Tolidaru Pharmaceuticals) does not improve ADHD symptoms compared to methylphenidate, a drug used to treat ADHD, in children 6-14 years-old.
- Autism. Research shows that taking a specific ginkgo extract (Ginko T.D. Tolidaru Pharmaceuticals) daily for 10 weeks along with conventional medication does not improve autism symptoms in children.
- A lung disease called chronic obstructive pulmonary disease (COPD). Research shows that taking a specific product that contains ginkgo extract, ginger, and Picrorhiza kurroa (AKL1, AKL International Ltd) twice daily for 8 weeks does not improve lung function in people with COPD.
- Cocaine addiction. Research suggests that taking a ginkgo leaf extract called EGb 761 twice daily for 10 weeks does not help people with a cocaine addiction.
- Colorectal cancer. Early research suggests that using a specific ginkgo leaf extract (EGb 761, ONC) intravenously (by IV) together with anticancer drugs might benefit people with colorectal cancer.
- Dyslexia. Early research suggests that taking a specific ginkgo leaf extract (EGb 761) can help reduce dyslexia in children aged 5-16 years.
- Fibromyalgia. Early research suggests that taking specific ginkgo leaf extract tablets (Bio- Biloba, Pharma Nord) together with coenzyme Q-10 capsules (Bio Quinone Q10, Pharma Nord) by mouth might increase feelings of wellness and perception of overall health and reduce pain in people with fibromyalgia.
- Stomach cancer. Early research suggests that taking carbohydrates from the outer layer of the ginkgo fruit by mouth twice daily for 30 days might reduce tumor size in people with stomach cancer.
- Hearing loss. There is some early evidence that taking ginkgo might help short-term hearing loss due to unknown causes. However, many of these people recover hearing on their own. It is hard to know if ginkgo has any effect.
- Hemorrhoids. Early research suggests that taking a combination of ginkgo and certain conventional medications might decrease some symptoms of hemorrhoids, including bleeding and pain.
- Migraine. Early research shows that taking ginkgolide B, a chemical found in ginkgo leaf extract, might help prevent migraines in children and women.
- Ovarian cancer. Evidence suggests that using ginkgo leaf extract is associated with a decreased risk of developing ovarian cancer.
- Pancreatic cancer. Early research suggests that taking a specific ginkgo leaf extract (EGb 761) intravenously (by IV) together with anticancer drugs might slow the progression of pancreatic cancer in some people.
- Quality of life. Early evidence suggests that taking ginkgo extract (LI 1370, Lichtwer Pharma) might improve quality of life measures such as activities in daily living, mood, sleep, and alertness in older people.
- Radiation exposure. Early research suggests that taking a specific ginkgo leaf extract (EGb 761, Tanakan Ipsen) might reduce some of the negative effects of radiation on the body.
- Skin toxicity caused by radiation. Early research suggests that applying a specific cream product (Radioskin 2, Herbalab di Perazza Massimiliano Company) that contains ginkgo extract, Aloe vera, and metal esculetina along with another product (Radioskin 1, Herbalab di Perazza Massimiliano Company) might improve skin moisture and reduce toxicity in breast cancer patients receiving radiation treatments.
- Blood vessel disorder (Raynaud's syndrome). Some research suggests that taking ginkgo leaf extract by mouth can decrease the number of painful attacks per week in people with a blood vessel disorder called Raynaud's syndrome. However, other research suggests that ginkgo is not beneficial or is less effective than drugs such as nifedipine.
- Sexual dysfunction. Some research shows that taking ginkgo leaf extract daily for 8 weeks does not improve sexual function in women with sexual arousal disorder. However, taking a specific combination product containing ginkgo, ginseng, damiana, L-arginine, multivitamins, and minerals (ArginMax for Women) appears to improve sexual satisfaction in women with sexual dysfunction.
- Stroke. There is contradictory evidence about the effectiveness of ginkgo for improving recovery in people with strokes caused by a clot. Some evidence suggests that people may improve more after a stroke when treated with ginkgo. However, other research shows no benefit.
- Skin discolorations (Vitiligo). There is some early research that taking a specific ginkgo leaf extract (Ginkgo Plus, Seroyal) might decrease the size and spread of skin lesions.
- High cholesterol.
- "Hardening of the arteries" (atherosclerosis).
- Blood clots.
- Thinking problems related to Lyme disease.
- Chronic fatigue syndrome (CFS).
- Bloody diarrhea.
- Urinary problems.
- Digestion disorders.
- Skin sores.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
Next: How does Ginkgo work?
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