VICUS.COM (14 April 2000) -- Ginkgo has been called a brain booster
by Lester Packer in his book, The Antioxidant Miracle.
In Germany and France, ginkgo is often prescribed to treat people with
difficulty concentrating, poor memory, confusion, depression or
anxiety. Ginkgo may also have a role in treating Alzheimer's
disease (Klepser, 1999).
Ginkgo is generally safe and well tolerated. Severe side effects
are rare. The most commonly reported adverse effects include stomach
upset, headache, dizziness, heart palpitations and vertigo (Klepser,
1999). A toxic syndrome known as "Gin-nan" food poisoning (tonic/clonic
seizures and loss of consciousness) can occur after taking 50
ginkgo seeds (Guide to Popular Natural Products, 1999).
The most potentially significant side effect associated with ginkgo
biloba is bleeding. Three cases have been reported in the
medical literature (Klepser, 1999). Although it is not known for sure
if the ginkgo was responsible, it is recommended that people avoid
combining ginkgo biloba with aspirin or anticoagulant medications such
as warfarin (Coumadin; Rosenblatt, 1997).
If ginkgo biloba is taken, it is important to remember some people
may not tolerate ginkgo even in small doses.
Recommendations for ginkgo consumption include:
- Do not use ginkgo if you have a blood-clotting
disorder, or if you are pregnant or nursing.
- Do not combine ginkgo biloba with drugs that may predispose you
to bleeding, such as aspirin or warfarin (Coumadin).
- Do not give ginkgo to children without a doctor's supervision.
- Use in medicinal amounts only in consultation with a health-care
- Tell your surgeon and anesthesiologist if you have been taking
Recommendations for dosing:
The recommended dosage may vary, depending on the reason for taking
ginkgo (indication). For indications related to mental function, the
German government's Commission E gives a dosing range of 120-240 mg
native dry extract daily, divided in two or three doses. A typical
schedule is 40 mg three times a day, with meals.
Response to ginkgo may take four to six weeks (Guide to Popular
Natural Products, 1999). As with many herbal preparations, it is
essential to choose a quality product and to consult with an
appropriate health-care provider, particularly if you take other
medications or have other significant health conditions.
Standardized preparations of ginkgo biloba contain 5% to 7% terpene
lactones and 22% to 27% ginkgo flavonone glycosides (Blumenthal,
John Russo, Jr., PharmD, is senior vice president of medical
communications at Vicus.com. He is a pharmacist and medical writer
with more than 20 years of experience in medical education.
Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine:
Expanded Commission E Monographs. Newton (MA): Integrative
Medicine Communications; 2000.
Guide to Popular Natural Products. St. Louis (MO): Facts and
Klepser TB, Klepser ME. Unsafe and potentially safe herbal
therapies. American Journal of Health-System Pharmacy.
McLeskey CH, Meyer T, Baisden CE, Gloyna DF, Roberson CR. The
incidence of herbal and selected nutraceutical use in surgical
patients (abstract). American Society of Anesthesiologists;
Packer L, Colman C. The Antioxidant Miracle. New York
(NY): John Wiley and Sons, Inc.; 1999.
Rosenblatt M, Mindel J. Spontaneous hyphema associated with
ingestion of Ginkgo biloba extract. New England Journal of
Medicine. 1997; 336(15):1108.