Ginkgo biloba extract: review of CNS effects.

The marketing of Ginkgo biloba extract (GBE) products is directed to the healthy, not diseased, population primarily for the promotion and maintenance of optimal brain function, not the treatment or prevention of any specific pathological state. However, recommendations are available for the use of GBE for a myriad of diseases that generally fall into one of three categories--cerebrovascular, peripheral vascular, or mitigation of tissue damage. The evidence for the pharmacological actions of GBE stem from one of three types of investigations--clinical studies in humans, pharmacological trials in animals, and in vitro studies. The purpose of this paper is to review the scientific literature on the central nervous system effects of GBE, with emphasis on the potential mechanisms of action. Limitations of the current scientific literature are highlighted and suggestions for future human and animal research directions are proposed.