Description

Ginkgo is a large tree with fan-shaped leaves. It is native to China, Japan, and Korea, but is also now grown in Europe and the United States. The ginkgo tree is thought to be one of the oldest living trees, dating back to more than 200 million years.

Ginkgo leaf is often taken by mouth for memory and thought problems, anxiety, vision problems, and many other conditions, but there is no good scientific evidence to support most of these uses.

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 BCE.

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.

How does it work?

Ginkgo seems to improve blood circulation, which might help the brain, eyes, ears, and legs function better. It may act as an antioxidant to slow down Alzheimer’s disease and interfere with changes in the brain that might cause problems with thinking.

Ginkgo seeds contain substances that might kill the bacteria and fungi that cause infections in the body. The seeds also contain a toxin that can cause serious side effects like seizures and loss of consciousness.

Uses & Effectiveness?

Possibly Effective for

• Anxiety. Research shows that taking a ginkgo extract for 4 weeks can reduce symptoms of anxiety.
• Diseases, such as Alzheimer disease, that interfere with thinking (dementia). Taking 240 mg of ginkgo daily may slightly improve dementia symptoms. But it’s unclear how ginkgo compares to conventional medicines used for dementia. Ginkgo doesn’t seem to prevent dementia from developing or getting worse.
• 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.
• High blood pressure in arteries in the lungs (pulmonary hypertension). Receiving ginkgo leaf extract plus the drug dipyridamole by IV seems to reduce symptoms and improve the amount of oxygen in the arteries in the lungs in people with pulmonary hypertension.
• Schizophrenia. Research shows that taking ginkgo daily in addition to conventional antipsychotic medications for 8-16 weeks can reduce symptoms of schizophrenia. It may also reduce some side effects like thirst and constipation and adverse effects associated with the antipsychotic medication, haloperidol.
• Stroke. Using ginkgo extract by mouth or receiving it by IV along with standard therapy seems to improve thinking, memory, and the ability to complete activities of daily living in people recovering from a stroke. Receiving ginkgo leaf extract plus dipyridamole by IV might also improve recovery after a stroke. But ginkgo doesn’t seem to lower the chance of death or having another stroke.
• A movement disorder often caused by antipsychotic drugs (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.) for 12 weeks can reduce the severity of tardive dyskinesia symptoms in people with schizophrenia who are taking antipsychotic drugs.
• Dizziness (vertigo). Taking ginkgo leaf extract by mouth seems to improve symptoms of dizziness and balance disorders.

Possibly Ineffective for

• Decline in memory and thinking skills that occurs normally with age. Most research shows that taking ginkgo doesn’t improve memory and thinking skills in elderly people.
• Sexual problems caused by antidepressants (antidepressant-induced sexual dysfunction). 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.
• Decline in memory and thinking skills in people treated with cancer drugs. 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 thinking problems caused by the chemotherapy in people being treated for breast cancer.
• Decline in memory and thinking skills in older people that is more than what is normal for their age. People with mild cognitive impairment (MCI) have a higher risk of dementia than people without MCI. Taking ginkgo doesn’t seem to prevent dementia in people with MCI.
• 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 (MS). 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 or SAD). 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 for

• An eye disease that leads to vision loss in older adults (age-related macular degeneration or AMD). There is some early evidence that ginkgo leaf extract might improve symptoms and distance vision in people with age-related vision loss.
• Hay fever. Early research shows that applying specific eye drops (Trium, SOOFT) that contain ginkgo extract and hyaluronic 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 (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). The effect of ginkgo on symptoms related to ADHD is unclear. There is early evidence that a product containing ginkgo leaf extract and American ginseng might help improve ADHD symptoms such as anxiety, hyperactivity, and impulsiveness in children 3-17 years-old. But other research shows that taking ginkgo extract does not improve ADHD symptoms compared to methylphenidate, a drug used to treat ADHD, in children 6-14 years-old. Also, taking gingko extract along with methylphenidate does not seem to greatly improve parent or teacher reported ADHD symptoms compared to methylphenidate alone in children 6-12 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 that makes it harder to breathe (chronic obstructive pulmonary disease or COPD). Research shows that taking a specific product that contains ginkgo extract, ginger, and Picrorhiza (AKL1, AKL International Ltd) twice daily for 8 weeks does not improve lung function in people with COPD.
• Cocaine use disorder. Research suggests that taking a ginkgo leaf extract called EGb 761 twice daily for 10 weeks does not help people with a cocaine addiction.
• Memory and thinking skills (cognitive function). The effect of gingko leaf extract on mental function and memory in healthy adults is not clear. Some research shows that ginkgo might improve memory, speed of thinking, and attention in healthy adults. But other research shows no benefit. More studies are needed to determine the effect of gingko on mental function in healthy adults.
• Colon cancer, rectal 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 advanced colorectal cancer.
• Depression. Early research shows that taking a specific ginkgo extract (Harbin HaoBo Pharmaceutical Co., Ltd.) with the antidepressant citalopram might improve depression in the elderly better than taking citalopram alone.
• Vision problems in people with diabetes (diabetic retinopathy). There is some evidence that taking ginkgo leaf extract by mouth for 6 months can improve color vision in people with retinal damage caused by diabetes.
• A learning disorder marked by difficulty reading (dyslexia). Early research suggests that taking a specific ginkgo leaf extract (EGb 761) for about 30 days might 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 for 84 days 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.
• A group of eye disorders that can lead to vision loss (glaucoma). There is mixed evidence about the effects of ginkgo for glaucoma. Some research shows that ginkgo improves vision. Other research shows no benefit.
• 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 for 6 months is associated with a decreased risk of developing ovarian cancer.
• Pancreatic cancer. Early research suggests that taking a specific injectable form of ginkgo leaf extract (EGb 761) intravenously (by IV) together with anticancer drugs might slow the progression of pancreatic cancer in some people.
• Narrowing of blood vessels that causes poor blood flow to the limbs (peripheral arterial disease). Taking ginkgo might improve walking in people with poor blood circulation in their legs. Taking ginkgo might also reduce the need for surgery. But it might take at least 24 weeks before improvements are seen.
• Quality of life. Early evidence suggests that taking ginkgo extract (LI 1370, Lichtwer Pharma) for 6 months 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 damage caused by radiation therapy (radiation dermatitis). Early research shows that applying a specific cream product (Radioskin 2, Herbalab di Perazza Massimiliano Company) that contains ginkgo extract and other ingredients along with another product (Radioskin 1, Herbalab di Perazza Massimiliano Company) might improve skin moisture and reduce skin adverse events in breast cancer patients receiving radiation treatments.
• Painful response to cold especially in the fingers and toes (Raynaud syndrome). Some research suggests that taking ginkgo leaf extract for 10 weeks by mouth might decrease the number of painful attacks per week in people with a blood vessel disorder called Raynaud syndrome. However, other research suggests that ginkgo is not beneficial or is less effective than drugs such as nifedipine.
• Sexual problems that prevent satisfaction during sexual activity. 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) for 4 weeks appears to improve sexual satisfaction in women with sexual dysfunction.
• A skin disorder that causes white patches to develop on the skin (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.
• Blood clots.
• Bloody diarrhea.
• Bronchitis.
• Chronic fatigue syndrome (CFS).
• Digestion disorders.
• Hardening of the arteries (atherosclerosis).
• High cholesterol.
• Thinking problems related to Lyme disease.
• Urinary problems.
• Scabies.
• Skin sores.
• Other conditions.

More evidence is needed to rate ginkgo for these uses.

Side Effects & Safety

When taken by mouth: Ginkgo LEAF EXTRACT is LIKELY SAFE for most people when taken by mouth in appropriate doses. 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 leaf extract might increase the risk of liver and thyroid cancers. But, this has only occurred in animals given extremely high doses of ginkgo. There is not enough information to know if it could happen in humans.

Ginkgo fruit and pulp can cause severe allergic skin reactions and irritation of mucous membranes. Ginkgo might cause an allergic reaction in people who are allergic to poison ivy, poison oak, poison sumac, mango rind, or cashew shell oil.

There is some concern that ginkgo leaf extract 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, brain, and lungs and excessive bleeding following surgery. Ginkgo leaf extract can cause allergic skin reactions in some people.

The ROASTED SEED or CRUDE GINKGO PLANT is POSSIBLY UNSAFE when taken by mouth. Eating more than 10 roasted seeds per day can cause difficulty breathing, weak pulse, seizures, loss of consciousness, and shock. The FRESH SEED is LIKELY UNSAFE when taken by mouth. Eating fresh ginkgo seeds could cause seizures and death. Fresh seeds are poisonous and are considered dangerous. Eating fresh ginkgo seeds could cause seizures and death.

When given by IV: Ginkgo LEAF EXTRACT is POSSIBLY SAFE when used intravenously (by IV), short-term. It has been used safely alone or in combination with the drug dipyridamole for up to 30 days.

When applied to the skin: There isn’t enough reliable information available to know if ginkgo is safe when applied to the skin.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Ginkgo is POSSIBLY UNSAFE when taken by mouth during pregnancy. It might cause early labor or extra bleeding during delivery if used near that time. Not enough is known about the safety of using ginkgo during breast-feeding. Do not use ginkgo if you are pregnant or breast-feeding.

Infants and children: Ginkgo leaf extract is POSSIBLY SAFE when taken by mouth for a short time. Some research suggests that a specific combination of ginkgo leaf extract plus American ginseng might be safe in children when used short-term. Do not let children eat the ginkgo seed. It is LIKELY UNSAFE. The fresh seeds have caused seizures and death in children

Bleeding disorders: Ginkgo might make bleeding disorders worse. If you have a bleeding disorder, don’t use ginkgo.

Diabetes: Ginkgo might interfere with the management of diabetes. If you have diabetes, monitor your blood sugar closely.

Seizures: There is a concern that ginkgo might cause seizures. If you have ever had a seizure, don’t use ginkgo.

Deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD): Ginkgo might cause severe anemia in people have G6PD enzyme deficiency. Until more is known, use cautiously or avoid using ginkgo if you have G6PD deficiency.

Infertility: Ginkgo use might interfere with getting pregnant. Discuss your use of ginkgo with your healthcare provider if you are trying to get pregnant.

Surgery: Ginkgo might slow blood clotting. It might cause extra bleeding during and after surgery. Stop using ginkgo at least 2 weeks before a scheduled surgery.

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