Ginkgo biloba

A tall ornamental deciduous tree of the family Ginkgoaceae with distinctive bilobed fan-shaped leaves; female trees bear edible seeds surrounded by a fleshy covering that when ripe smells strongly of butyric acid; native to China, but extinct in the wild, surviving only in cultivation; extracts of the leaves contain ginkgoheterosides and terpene lactones and are used medicinally in cerebral and peripheral vascular disease. SYN: maidenhair tree.The leaves of the ginkgo tree have been used in Chinese and Japanese traditional medicine for many centuries in diseases of the brain, heart, and lungs. Several well-controlled studies have shown that ginkgo extracts enhance both cerebral and peripheral blood flow in some vascular insufficiency syndromes. They have relieved symptoms in dementia, vertigo, and tinnitus of vascular origin and in intermittent claudication and premenstrual syndrome. Ginkgo extracts also inhibit platelet aggregation and scavenge free radicals. The usual dosage is 120–240 mg/day in 2–3 divided doses. Administration for several weeks may be required before beneficial effects are noted. Although G. biloba is promoted as a “smart pill” by purveyors of herbal remedies, it does not improve mental function in persons without cerebrovascular disease. Side effects are uncommon and include gastrointestinal upset, headache, and rash. A few cases of subarachnoid hemorrhage and hyphema have been reported, particularly in persons also taking aspirin. Administration of ginkgo extract should be discontinued before surgery.

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gink·go bi·lo·ba 'giŋ-(.)kō-.bī-'lō-bə,also 'giŋk-(.)gō- n an extract of the leaves of the ginkgo (Ginkgo biloba) that is used as a dietary supplement and is held to enhance mental functioning by increasing blood circulation to the brain called also ginkgo

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the sole species of the genus. The leaves and seeds are used medicinally; see ginkgo (def. 2). The foul-smelling pulp around the seeds contains urushiol and can cause urushiol dermatitis in susceptible individuals.