Ginkgo Flavone Glycoside

The flavonoid fraction of Ginkgo biloba leaf extract contains glycosides of quercetin, kaempferol, and isorhamnetin. These compounds have antioxidant activity in laboratory settings, and the standardized extract (most often EGb 761) is thought to support cerebral microcirculation and reduce oxidative stress. In the body, glycosides are hydrolyzed to their aglycones and absorbed, then largely metabolized in the liver. Flavone glycoside content is used as a quality marker but is not the sole active component of ginkgo; the terpene lactones (ginkgolides and bilobalide) also contribute.

Most clinical trials use standardized extract EGb 761 at 120-240 mg/day, which delivers approximately 28-58 mg/day of flavone glycosides at the 24% standardization.

Typically taken in two divided doses with meals to improve absorption and reduce GI upset. Effects on cognitive symptoms generally require weeks of consistent use.

Standardized ginkgo extract is generally well tolerated. Mild side effects include headache, GI upset, and dizziness. The most notable concern is increased bleeding risk, especially when combined with anticoagulants.

Ginkgo may increase bleeding risk in combination with warfarin, DOACs, antiplatelet drugs, and NSAIDs. It may also affect levels of seizure medications, antidepressants, and drugs metabolized by certain cytochrome P450 enzymes.