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Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020

Ginkgo is derived from the leaves of the ginkgo tree (commonly planted for ornamental purposes). The leaves contain numerous biologically active substances, such as ginkgolides and flavonoids. Ginkgo is one of the most commonly used herbal supplements.

The fruit of the ginkgo tree is not used in ginkgo products because of its bad smell. Contact with the fruit pulp, which may be encountered under female ginkgo trees, can cause severe skin inflammation (dermatitis). The seeds of the fruit are toxic and can cause seizures and, in large amounts, death.

Medicinal claims

Ginkgo reduces the clotting tendency of particles in the blood that help stop bleeding (platelets), dilates blood vessels (thereby improving blood flow), and reduces inflammation. People take ginkgo for many reasons, such as improving blood flow to the lower legs in people with atherosclerotic vascular disease of the arteries in the legs (peripheral arterial disease Overview of Peripheral Arterial Disease Peripheral arterial disease results in reduced blood flow in the arteries of the trunk, arms, and legs. Most often, doctors use the term peripheral arterial disease to describe poor circulation... read more Overview of Peripheral Arterial Disease ) and treating dementia (as in Alzheimer disease Alzheimer Disease Alzheimer disease is a progressive loss of mental function, characterized by degeneration of brain tissue, including loss of nerve cells, the accumulation of an abnormal protein called beta-amyloid... read more ). Scientific studies show ginkgo benefits people with peripheral arterial disease, although the benefit is minor. Ginkgo increased the distance that affected people could walk without pain. Major benefits for people with dementia seems unlikely based on findings from a large clinical trial. In this clinical trial, ginkgo was not effective in reducing the development of dementia and Alzheimer disease in older people. However, other studies indicate that ginkgo, when taken at sufficient doses and for more than 5 months, can temporarily stabilized mental and social function in people with mild to moderate dementia.

Studies show ginkgo may help to slow age-related macular degeneration Age-Related Macular Degeneration (AMD or ARMD) Age-related macular degeneration (AMD) causes progressive damage to the macula, the central and most vital area of the retina, resulting in gradual loss of central vision. Central vision becomes... read more Age-Related Macular Degeneration (AMD or ARMD) , which is an eye disease. Earlier evidence showed ginkgo helped relieve ringing in the ears (tinnitus) but more recent information indicates it does not help people whose main problem is tinnitus. Ginkgo may prevent altitude sickness Altitude Illness Altitude illness occurs because of a lack of oxygen at high altitudes. Symptoms include headache, tiredness, nausea or loss of appetite, irritability, and in more serious cases, shortness of... read more in some people. Ginkgo may prevent damage to the kidneys caused by the drug cyclosporine, which suppresses the immune system.

Possible side effects

Nausea, digestive upset, headache, dizziness, and heart palpitations may occur.

Possible drug interactions

Ginkgo may interact with drugs that prevent blood clots, aspirin, and other nonsteroidal anti-inflammatory drugs (NSAIDs). Ginkgo may also reduce the effectiveness of antiseizure drugs Antiseizure drugs In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more .

More Information about Ginkgo

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

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