Ginkgo (Ginkgo biloba)

Ginkgo biloba, commonly known as ginkgo or gingko, is a tree species native to China, but has been cultivated worldwide for several hundred years. The Gingko is the last living species of the order Ginkgoales, which originated over 290 million years ago. Therefore, it is also called a "living fossil".

Extracts for medicinal use are produced from the leaves of the ginkgo tree. These extracts are said to have a positive effect on brain performance and memory. It is also used to relieve dizziness and ringing in the ears. However, there is no scientific evidence to support these effects. Systematic reviews have shown that there is also no scientific evidence of efficacy in the treatment of hypertension, menopause-related cognitive decline, tinnitus, or altitude sickness. However, there is weak evidence that ginkgo affects dementia and tardive dyskinesia symptoms in people with schizophrenia.

Pharmacodynamics

An important group of substances contained in Ginkgo biloba are the so-called flavonoids. These activate the enzyme PAF (platelet-activating factor) and thus have an inhibitory effect on inflammation. In addition, flavonoids have radical scavenging properties. However, these two effects do not explain any effect on memory and concentration. It is assumed that mechanisms influencing the gene expression of antioxidative enzymes and the synthesis of proteins are responsible. However, whether Ginkgo biloba extracts are actually clinically effective remains unclear and is still being researched.

Interactions

The dosage of anticoagulants such as warfarin or antiplatelet agents may be affected by the use of Ginkgo supplements.

Side effects

Although taking standardized Ginkgo biloba leaf extracts in moderate amounts appears to be safe, excessive use may cause adverse effects.

Possible side effects include:

• Increased risk of bleeding
• Gastrointestinal symptoms
• Nausea
• Vomiting
• Diarrhea
• Headache
• Dizziness
• Palpitations
• Restlessness