Geological records indicate that ginkgo has been growing on earth for 150 - 200 million years. Ginkgo was first brought to Europe in the 1700's and is now a commonly prescribed drug in France and Germany. Ginkgo biloba extract is reported to inhibit blood platelet aggregation, and it is also an antioxidant. (Lancet, 340, 1136-1139, 1992).
The primary clinical application ginkgo biloba is in the treatment of impaired blood flow to certain parts of the body, mainly, the brain. It is speculated that the extract may aid in mental performance and help symptoms, such as, short-term memory loss, vertigo, headache, ringing in the ears, and depression. The Taoist Peng Zu who took ginkgo, and was said to have been 767 years old in 1123 BC, is reported to have finally died from boredom.
There are no large-scale or well-controlled studies examining the effects of ginkgo. A study in 1997 showed a slight slowing of cognitive decline in some patients with mild to moderately severe dementia. Because 60 percent of the people did not complete the study, the findings are difficult to interpret. There is no evidence that ginkgo biloba can cure or prevent Alzheimer's disease. (JAMA 1997; 278:1327).
Ginkgo may cause increased bleeding, especially in people taking warfarin, heparin, and possibly aspirin. The most common side effects reported include gastrointestinal discomfort, headache, and dizziness.