Ginkgo 

This fact sheet provides basic information about the herb ginkgo—common 

names, uses, potential side effects, and resources for more information. The 

ginkgo tree is one of the oldest types of trees in the world. Ginkgo seeds have 

been used in traditional Chinese medicine for thousands of years, and cooked 

seeds are occasionally eaten. 

Common Names—ginkgo, Ginkgo biloba, fossil tree, maidenhair tree, Japanese 

silver apricot, baiguo, bai guo ye, kew tree, yinhsing (yin-hsing) 

Latin Name—Ginkgo biloba 

What It Is Used For 

•	 Ginkgo leaf extract has been used to treat a variety of ailments and conditions, 

including asthma, bronchitis, fatigue, and tinnitus (ringing or roaring sounds in 

the ears). 

•	 Today, people use ginkgo leaf extracts hoping to improve memory; to treat or 

help prevent Alzheimer’s disease and other types of dementia; to decrease 

intermittent claudication (leg pain caused by narrowing arteries); and to treat 

sexual dysfunction, multiple sclerosis, tinnitus, and other health conditions. 

How It Is Used 

Extracts are usually taken from the ginkgo leaf and are used to make tablets, 

capsules, or teas. Occasionally, ginkgo extracts are used in skin products. 

What the Science Says 

•	 Numerous studies of ginkgo have been done for a variety of conditions. 

Some promising results have been seen for intermittent claudication, but 

larger, well-designed research studies are needed. 

•	 An NCCAM-funded study of the well-characterized ginkgo product, EGb-761, 

found it ineffective in lowering the overall incidence of dementia and 

Alzheimer’s disease in the elderly. In this clinical trial, known as the Ginkgo 

Evaluation of Memory study, researchers recruited more than 3,000 

volunteers age 75 and over who took 240 mg of ginkgo daily. Participants 

were followed for an average of approximately 6 years. 

•	 Some smaller studies for memory enhancement have had promising results, but 

a trial sponsored by the National Institute on Aging of more than 200 healthy 

adults over age 60 found that ginkgo taken for 6 weeks did not improve memory. 

•	 Other NCCAM-funded research includes studies on ginkgo for asthma, 

symptoms of multiple sclerosis, vascular function (intermittent 

claudication), cognitive decline, sexual dysfunction due to antidepressants, 

and insulin resistance. NCCAM is also looking at potential interactions 

between ginkgo and prescription drugs. 
 

Side Effects and Cautions 

•	 Side effects of ginkgo may include headache, nausea, gastrointestinal upset, diarrhea, dizziness, 

or allergic skin reactions. More severe allergic reactions have occasionally been reported. 

•	 There are some data to suggest that ginkgo can increase bleeding risk, so people who take 

anticoagulant drugs, have bleeding disorders, or have scheduled surgery or dental 

procedures should use caution and talk to a health care provider if using ginkgo. 

•	 Uncooked ginkgo seeds contain a chemical known as ginkgotoxin, which can cause 

seizures. Consuming large quantities of seeds over time can cause death. Ginkgo leaf and 

ginkgo leaf extracts appear to contain little ginkgotoxin. 

•	 Tell your health care providers about any complementary and alternative practices you 

use. Give them a full picture of what you do to manage your health. This will help ensure 

coordinated and safe care. 

Sources 

DeKosky ST, Williamson JD, Fitzpatrick AL, et al. Ginkgo biloba for prevention of dementia: a randomized controlled 


trial. Journal of the American Medical Association. 2008;300(19):2253-2262.
 

De Smet PA. Herbal remedies. New England Journal of Medicine. 2002;347(25):2046-2056.
 

Solomon PR, Adams F, Silver A, et al. Ginkgo for memory enhancement: a randomized controlled trial. Journal of the 


American Medical Association. 2002;288(7):835-840. 


Ginkgo biloba. In: Coates P, Blackman M, Cragg G, et al., eds. Encyclopedia of Dietary Supplements. New York, NY: Marcel 


Dekker; 2005:249-257.
 

Ginkgo. Natural Medicines Comprehensive Database Web site. Accessed at http://www.naturaldatabase.com on July 2, 2007.
 

Ginkgo (Ginkgo biloba L.). Natural Standard Database Web site. Accessed at http://www.naturalstandard.com on June 28, 2007.
 

Ginkgo biloba leaf extract. In: Blumenthal M, Goldberg A, Brinckman J, eds. Herbal Medicine: Expanded Commission E 


Monographs. Newton, MA: Lippincott Williams & Wilkins; 2000:359-366.
 

For More Information 

Visit the NCCAM Web site at nccam.nih.gov and view: 

•	 What’s in the Bottle? An Introduction to Dietary Supplements at nccam.nih.gov/health/bottle/ 

•	 Herbal Supplements: Consider Safety, Too at nccam.nih.gov/health/supplement-safety/ 

NCCAM Clearinghouse 

Toll-free in the U.S.: 1-888-644-6226 

TTY (for deaf and hard-of-hearing callers): 1-866-464-3615 

E-mail: info@nccam.nih.gov 

CAM on PubMed 

Web site: nccam.nih.gov/camonpubmed/ 

NIH Office of Dietary Supplements 

Web site: www.ods.od.nih.gov 

NIH National Library of Medicine’s MedlinePlus 

Ginkgo Listing: www.nlm.nih.gov/medlineplus/druginfo/natural/patient-ginkgo.html 

This publication is not copyrighted and is in the public domain. Duplication is encouraged. 

NCCAM has provided this material for your information. It is not intended to substitute for the medical 

expertise and advice of your primary health care provider. We encourage you to discuss any decisions 

about treatment or care with your health care provider. The mention of any product, service, or therapy 

is not an endorsement by NCCAM. 

National Institutes of Health 

♦♦♦

U.S. Department of Health and Human Services 

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Created September 2005 

Updated November 2008 

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