More than 400 published studies have been conducted using Ginkgo Biloba extract (GBE), making it one of the most studied of all herbal medicines. In Germany and France it is the most frequently prescribed herbal medicine and ranks within the top five of all prescriptions written in those countries. GBE is a powerful aid to circulatory problems, particularly a lack of blood to the brain that may be associated with memory loss, vertigo, tinnitus, disorientation, headaches, and depression, especially in the elderly. Patients suffering from leg cramps due to poor circulation have also experienced good results with GBE. Ginkgo has strong antioxidant properties as well, which may protect both the central nervous system and the cardiovascular system from damage and the effects of aging. Results from an animal study suggest that the antioxidants in ginkgo may also protect against high blood pressure. These findings may warrant further research in humans.

GBE improves blood circulation by reducing the stickiness of blood platelets. This improves blood flow to the brain and limbs, and may prevent or treat heart disease as well as stroke. Ginkgo may also be effective in preventing the onset of age-related mental deterioration. GBE is most often recommended for older people suffering from signs of dementia. In a few small studies, GBE seemed to delay the progression of Alzheimer's disease, particularly in the early stages. In addition, use of an herbal tincture containing a combination of ginkgo, St. John's wort, and rosemary may improve cognitive impairment as well as visual and speech disturbances that may be associated with recovery from brain inflammation (viral encephalitis). Ginkgo may also be useful for treating attention deficit/hyperactivity disorder.

For men's health, GBE is being studied as an aid for impotence caused by impaired blood flow. The combination of ginkgo and papaverine has reportedly been effective for the treatment of erectile dysfunction. Ginkgo may also have applications for women's health. Specifically, ginkgo may help reduce certain premenstrual symptoms such as fluid retention and breast tenderness.

Ginkgo biloba is the oldest living tree species. It is amazingly adaptable, surviving even the Ice Age and the atomic bomb that destroyed Hiroshima. A single tree can live as long as 1,000 years and grow to a height of 120 feet. It has short branches with fan-shaped leaves and produces inedible fruit that has a strong odor. The fruit contains an edible inner seed. Although Chinese herbal medicine has used both the ginkgo leaf and seed for centuries, modern research has focused on the standardized Ginkgo biloba extract (GBE), which is produced from the leaves. This extract is highly concentrated and much more effective than any other product made from the leaves.

Ginkgo biloba is made up of ginkgo flavone glycosides, several terpene molecules unique to ginkgo (ginkgolides and bilobalide), and organic acids. The special terpene molecules are thought to give Ginkgo biloba its ability to fight many of the effects of aging. This includes improving blood circulation, reducing inflammation, and protecting brain cells from damage caused by lack of oxygen.

Ginkgo biloba extract standardized to contain 24% ginkgo flavone glycosides (50:1 extract) and 6% terpene lactones. Capsules and tincture are also available.

How to Take It 

Pediatric

There are no known scientific reports to date about the use of ginkgo in children.

Adult

Initial results often take four to six weeks, but should continue to accumulate beyond that period. You may not see any dramatic changes for six months.

• 120 mg daily in two or three divided doses of 50:1 extract standardized to 24% flavone glycosides. If more serious dementia or Alzheimer's disease is present, up to 240 mg daily in two or three divided doses may be necessary.
• Tincture (1:5): 2 to 4 mL three times a day

GBE is considered to be safe and side effects are rare. In a few cases, gastrointestinal upset, headaches, and dizziness were reported. GBE does not appear to alter heart rate and blood pressure or to change cholesterol and triglyercide levels. Because it decreases platelet aggregation (stickiness), there is some concern that ginkgo may increase risk of intracranial (brain) hemorrhage. Use with caution in conjunction with other blood-thinning agents (for example, warfarin). Do not handle or ingest the fruit of Ginkgo biloba. The German Commission E reports that a hypersensitivity to Ginkgo biloba preparations is the only known reason not to take GBE.

If you are pregnant, you should exercise caution since there is a lack of data concerning GBE's effect during pregnancy. Do not give GBE to infants or children.

Ginkgo has blood-thinning properties and therefore should not be used if you are taking anticoagulant (blood-thinning) medications, such as aspirin, clopidogrel, dipyridamole, heparin, ticlopidine, or warfarin.

High doses of Ginkgo biloba could decrease the effectiveness of anticonvulsant therapy in patients taking carbamazepine or valproic acid to control seizures. If you are taking these medications, you should not use gingko without consulting your health care provider.

Ginkgo biloba may be beneficial during treatment with cyclosporine because of its ability to protect cell membranes from damage. If you are currently taking cyclosporine, you should consult your doctor before adding any new herbs or supplements to your existing medication regimen.

The combination of papaverine and ginkgo may be effective for the treatment of erectile dysfunction in patients who do not respond to papaverine alone. Consult with your doctor about whether this is an appropriate treatment option for you.

Although there has been one literature report of increased blood pressure associated with the use of ginkgo during treatment with thiazide diuretics, this interaction has not been verified by clinical trials. Nevertheless, you should consult with your healthcare provider before using ginkgo if you are taking thiazide diuretics.

Additionally, there has been a report of an adverse interaction between ginkgo and trazodone, an antidepressant medication, that resulted in an elderly patient going into a coma. Therefore, you should not take ginkgo if you are taking trazodone for depression without consulting with your doctor first.

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