Ginkgo Biloba, Memory and Stroke Risk

Ginkgo Biloba is one of the most popular supplements. It is used to improve memory and prevent cognitive problems such as dementia. As the population ages, researchers are looking for ways to help keep the minds of older adults healthy. One of the possibilities is ginkgo biloba.

Ginkgo Biloba and Memory Loss

Researchers enrolled 118 people over age 85 with no memory or other cognitive problems in a study, published in 2008 in the journal Neurology, to find out the impact of ginkgo biloba on memory and dementia. Half of the people took a ginkgo biloba supplement three times a day, and the other half took a placebo. Researchers followed up with them for three years. Over the course of the study, 21 people developed mild memory problems; 14 of those people were taking the placebo, and seven were taking to ginkgo extract. But it's not all good news for ginkgo. The difference between the ginkgo and placebo groups was not statistically significant. In other words, the fact that the placebo group had more cases of memory problems could have been just random change.

Dosage and Adherence in Ginkgo Biloba Supplementation

The researchers also found that some of the people in the ginkgo biloba group were not following dosage directions. When the people who were not taking their ginkgo biloba three times daily were removed from the analysis, the remaining ginkgo biloba takers had 68% less risk of developing mild memory problems over three years.

Ginkgo Biloba and Stroke Risk

But then there’s some bad news again: The group taking the ginkgo biloba extract had more strokes and mini-strokes than the placebo group. Researchers concluded that more research needs to be done to better understand the benefits and risks of ginkgo biloba and brain health.

Should I Take Ginkgo Biloba?

Right now, it doesn’t seem like a good idea. There could be something to the claims that ginkgo biloba can improve memory (or at least slow memory decline), but the evidence isn’t strong enough, and the possible increase in stroke risk is just too high. There are also multiple forms of ginkgo biloba in the marketplace. Until researchers figure out which forms are harmful and in what dosage, it seems best to stay away. Instead of looking for a pill, consider these mental fitness techniques to keep your brain sharp.

Ginkgo biloba

What is Gingko Biloba?

Alternate names: Maidenhair tree, Kew tree, Japanese silver apricot

Ginkgo is one of the oldest living tree species. The extract of ginkgo leaves is used medicinally in North America, where it's one of the most popular medicinal herbs, and many other countries around the world. In traditional Chinese medicine, the seeds of the ginkgo tree are used.

Why Do People Use Ginkgo?

• To improve mental function
  
• Alzheimer's disease
  
• Age-related memory loss
  
• Macular degeneration
  
• Sexual dysfunction
  
• To enhance blood circulation

Ginkgo leaves are believed to contain compounds that thin blood and help to improve muscle tone in the walls of blood vessels. This may enhance blood flow.

What are the Safety Concerns?

Constituents in ginkgo leaves may affect blood clotting, so ginkgo leaf extracts shouldn't be used by people with bleeding disorders. People with epilepsy (or anyone with a history of seizures) should avoid ginkgo, because it may increase the frequency of seizures.

Ginkgo leaf products may affect blood sugar levels, so people with diabetes should only be used under the supervision of a health care provider.

The safety of ginkgo in pregnant or nursing women and children isn't known.

What are the Side Effects of Ginkgo?

Side effects of ginkgo leaf include excessive bleeding. Rarely, seizures have been reported in people using either the ginkgo leaf or seed. Other side effects include digestive problems, headaches, allergic skin reactions, or muscle weakness.

People should not consume fresh ginkgo seeds. Roasted ginkgo seeds may cause diarrhea, nausea, indigestion, vomiting, or allergic skin reactions. Side effects of fresh ginkgo seeds or over 10 roasted ginkgo seeds may include difficulty breathing, seizures, unconsciousness and death.

Possible Drug Interactions

Ginkgo can increase the effect of blood-thinners (antiplatelet or anti-clotting drugs), such as clopidogrel, ticlopidine (Ticlid), warfarin (Coumadin), heparin, and aspirin, which may result in uncontrolled bleeding or hemorrhage. Certain herbs, such as danshen, devil's claw, eleuthero, garlic, ginger, horse chestnut, papain, red clover, and saw palmetto, can also increase the risk of bleeding if combined with ginkgo.

Ginkgo has been found to interfere with the metabolism of drugs processed by an enzyme called cyp3A4. Ask your doctor to check if you are taking medications of this type.

Ginkgo may increase the risk of seizures if combined with other drugs or herbs that do the same, such as antidepressants, bupropion (Wellbutrin, Zyban), certain antibiotics such as penicillin and cephalosporins, Corticosteroids, fentanyl (Actiq, Duragesic), theophylline, methylphenidate (e.g. Concerta, Ritalin), drugs that suppress the immune system, such as azathioprine and cyclosporine, borage, evening primrose, and wormwood.

Ginkgo shouldn't be used with the drug cyclosporine (used to suppress the immune system), because it has been found to decrease the effect of that drug. Theoretically, ginkgo may have the same effect with other immunosuppressant drugs.

Ginkgo may interact with insulin and other drugs for diabetes, such as metformin (Glucophage), glyburide (Glynase), glimepiride (Amaryl), and glipizide (Glucotrol XL). It shouldn't be used with medications to prevent seizures.