The standardized extract (EGb 761) contains flavone glycosides (24%) and terpene lactones (6%, ginkgolides and bilobalide). Mechanisms include: increased cerebral blood flow, platelet-activating factor (PAF) antagonism, antioxidant activity, and neuroprotective effects. The PAF antagonism is why ginkgo increases bleeding risk, it literally blocks platelet activation.
PAF antagonism → increased bleeding risk; case reports of hemorrhage
Additive antiplatelet effects → bleeding risk
Ginkgo has serotonergic properties; additive effects + bleeding risk
May reduce seizure threshold (controversial)
In vitro CYP induction; clinical significance variable
May reduce alprazolam levels via CYP3A4 induction
Case report of coma when combined with ginkgo
Discontinue ginkgo at least 2 weeks before surgery due to antiplatelet effects.
Not Prohibited
Reference identifiers on this page are being re-verified against PubMed. Some may not yet link to the paper named beside them.
, DeKosky ST et al. Ginkgo biloba for prevention of dementia (GEM study). *JAMA.* 2008.
(2008). PMID: 19017911
Independently graded against 178,763 indexed supplements and 757 reviewed supplement and medication pairs, sourced from PubMed, FDA CAERS, openFDA, and NIH DSLD | Last updated: April 2026
Not medical advice. Based on published clinical research and systematic reviews.
Safety
Warfarin and other anticoagulants
Two controlled studies in healthy volunteers found ginkgo did not alter warfarin pharmacokinetics or INR. Bleeding case reports exist; stop before surgery and tell your clinician. For DOACs no study exists and the same low posture applies (mechanism_inference).
Ginkgolides inhibit platelet activating factor (PAF). Case reports document spontaneous bleeding (intracranial, subdural, retinal) in patients on warfarin plus Ginkgo.
Aspirin and NSAIDs
Increased risk of bleeding and abnormal coagulation profiles.
Ginkgo biloba extract inhibits platelet-activating factor (PAF), leading to synergistic antiplatelet effects when combined with antiplatelet drugs.
Case reports of bleeding events. Monitor for unusual bleeding when combining.
Ginkgolides inhibit platelet activating factor (PAF). Additive antiplatelet effect with aspirin's COX-1 inhibition.
CYP2C9 substrates
Possible minor additive vascular effects. Monitor if combined with other antiplatelet or antihypertensive agents.
Ginkgo biloba has mild vasodilatory and antiplatelet activity. Generally minor interaction with Losartan.
Seizure medications (valproate, phenytoin)
Basis: Case reports
Stop 2 weeks before surgery
Bleeding risk from PAF inhibition.
Educational information only. This is not medical advice. These statements have not been evaluated by the FDA. Talk to your prescriber before starting, stopping, or combining any supplement with prescription medication.