Dietary supplements Ginkgo biloba

Patients should also be questioned about the use of any medications that might impair clotting. These might include prescription medications such as warfarin or over-the-counter medications such as aspirin. Even dietary supplements such as ginkgo biloba may have potential impact on bleeding. Consultation with the patient s physician is necessary to approve discontinuation of any prescribed anticoagulation agent. 

Many herbal drugs, amino acids, and hormones are marketed as dietary supplements. They include areca, DHEA, ephedra, ginkgo biloba, kava, melatonin, SAMe, Salvia divinorum, St. John s wort, and valerian. 

Ginkgo biloba (GB) is sold as a dietary supplement in the United States. It is purported to improve blood flow to the brain and to improve peripheral circulation. It is promoted mainly to sharpen mental focus in otherwise healthy adults as well as in those with dementia. Other conditions for which it is currently used are diabetes-related circulatory disorders, impotence, and vertigo. 

Li, W., J.F. Fitzloff, N.R. Farnsworth, and H.H. Fong. 2002a. Evaluation of commercial Ginkgo biloba dietary supplements for the presence of colchicine by high-performance liquid chromatography. Phytomedicine 9(5) 442-446. 

Yoshioka, M., N. Ohnishi, T. Koishi, et al. 2004. Studies on interactions between functional foods or dietary supplements and medicines. IV. Effects of Ginkgo biloba leaf extract on the pharmacokinetics and pharmacodynamics of nifedipine in healthy volunteers. Biol. Pharm. Bull. 27(12) 2006-2009. 

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