Ginkgo biloba (often referred to as ginkgo) is an herb made from the leaves of the ginkgo biloba tree – the oldest living tree species on earth. The tree is native to China, where its extracts have been used for centuries as a tonic to treat a variety of conditions including asthma and digestive disorders. Today, ginkgo is sold as an herbal supplement in the United States and taken as a complementary and alternative medicine (CAM) therapy for dementia, early stage Alzheimer’s disease and leg pain associated with blocked arteries.

Ginkgo biloba has been researched extensively in Europe, where it is sold as a prescription medication. Clinical trials continue on ginkgo’s many purported properties for health and wellness, but the herb is thought to have three basic functions:

• Improving blood flow throughout the body (especially in the brain)
  
  
• Blocking the effects of platelet activating factor, which may affect blood clotting and inflammation
  
  
• Acting as an antioxidant by removing oxygen free radicals that damage cells throughout the body

The herb is generally considered safe. However, people who use ginkgo may be at greater risk of bleeding. Patients undergoing surgical procedures (including certain dental procedures) are strongly urged to stop taking ginkgo biloba at least three weeks before a procedure to avoid complications or excessive bleeding.  Minor side effects associated with ginkgo include headache, nausea and gastrointestinal complaints.

Ginkgo may cause interactions with over-the-counter medications, prescriptions drugs, foods or other herbal supplements. This can cause serious complications, especially for patients with existing medical conditions (e.g., hemophilia, diabetes and hypoglycemia). Because ginkgo biloba affects blood’s clotting abilities, its most potent interactions may be associated with prescription anticoagulant medications. The herb is not recommended for pregnant or breastfeeding women or for children under 18. Patients considering ginkgo biloba should consult their physician first.

Ginkgo is sold in pill, caplet, tablet, liquid and powder form. These products are typically made from a leaf extract that is standardized. Ginkgo seeds are sometimes used in cooking, but eating them raw is not recommended. The seeds contain a toxin which can cause seizures, loss of consciousness, and even death. There have been rare cases of death after small children ate the seeds.

Ginkgo is widely used in Europe, especially France and Germany. In the United States, the herb is not regulated by the U.S. Food and Drug Administration (FDA) for quality or effectiveness. Nevertheless, ginkgo is one of the most popular herbal supplements sold.