Ginkgolide B

Ginkgolide B at a Glance

Ginkgolide B is a diterpene trilactone of Ginkgo biloba and one of the most structurally remarkable molecules in plant chemistry — a caged, six-ring system that was a landmark of total synthesis.

Pharmacologically it is the prototypical selective platelet-activating-factor (PAF) receptor antagonist, developed under the drug code BN52021. PAF drives platelet aggregation and inflammatory signalling, and ginkgolide B was the tool compound that defined the receptor.

Its human evidence as an isolate is mechanistic; the encouraging clinical work is on ginkgo extracts.

What It's Used For

Ginkgolide B (GB) is a diterpene trilactone of Ginkgo biloba and the prototypical selective antagonist of the platelet-activating-factor (PAF) receptor — its research drug code is BN52021 ^{1Reference 1DeFeudis FV · 2000Ginkgo biloba extract (EGb 761) and CNS functions: basic studies and clinical applicationsView study →}.

The single most important framing point is a naming distinction that the page keeps sharp throughout: nearly all the encouraging human data attributed to “ginkgolide B” are actually for ginkgo diterpene lactone meglumine (GDLM), an injectable mixture of ginkgolides A/B/C (plus bilobalide) used clinically in China for ischemic stroke ^{3Reference 3Zhang Q et al. · 2023RCTEfficacy and safety of ginkgo diterpene lactone meglumine in acute ischemic stroke: a randomised clinical trialView study →} — not the purified oral molecule, and not the whole leaf extract EGb 761. Isolated GB’s own human evidence is mechanistic (antiplatelet, historical anti-asthma) ^{2,13Reference 2Liu Y et al. · 2014Ginkgolide B inhibits platelet release by blocking Syk and p38 MAPK phosphorylation in thrombin-stimulated plateletsView study →Reference 13Hsieh KH · 1991Effects of the PAF antagonist BN52021 on PAF-, methacholine- and allergen-induced bronchoconstriction in asthmatic childrenView study →}.

Its defining mechanism — PAF antagonism — underlies both its circulatory effects and its (contested) bleeding-risk signal.

Evidence by IndicationStrength of support · Beta

Support is an experimental score — weighted by study type (human > animal > in vitro) and volume. A beta, not a validated metric. The human data are for the injection mixture, not the isolate, so isolate scores stay low by design. Each application links to its write-up.

01Ischemic stroke (injection mixture)Shaky40%RCTs of the GDLM mixture, not isolated GB ^{3,4,6Reference 3Zhang Q et al. · 2023RCTEfficacy and safety of ginkgo diterpene lactone meglumine in acute ischemic stroke: a randomised clinical trialView study →Reference 4Chen C et al. · 2023RCTAntiplatelet effect of ginkgo diterpene lactone meglumine injection in acute ischemic stroke: a randomised controlled trialView study →Reference 6Wang L et al. · 2025Meta-analysisGinkgo diterpene lactone meglumine for functional recovery in acute ischemic stroke: a systematic review and meta-analysisView study →}

02PAF antagonism (antiplatelet / asthma)Shaky30%Isolated GB/BN52021 pharmacology + one small asthma study ^{1,2,13Reference 1DeFeudis FV · 2000Ginkgo biloba extract (EGb 761) and CNS functions: basic studies and clinical applicationsView study →Reference 2Liu Y et al. · 2014Ginkgolide B inhibits platelet release by blocking Syk and p38 MAPK phosphorylation in thrombin-stimulated plateletsView study →Reference 13Hsieh KH · 1991Effects of the PAF antagonist BN52021 on PAF-, methacholine- and allergen-induced bronchoconstriction in asthmatic childrenView study →}

03Anti-inflammatoryShaky22%Preclinical rodent/cell only ^{14,16Reference 14Gu JH et al. · 2012AnimalInhibition of NF-κB activation is associated with anti-inflammatory and anti-apoptotic effects of ginkgolide B in a mouse model of cerebral ischemia/reperfusion injuryView study →Reference 16Feng Z et al. · 2019ReviewThe neuroprotective mechanisms of ginkgolides and bilobalide in cerebral ischemic injury: a literature reviewView study →}

04CognitiveShaky16%Exploratory arm of the stroke-injection trials ^{5Reference 5Zhang M et al. · 2024Clinical trialEffectiveness of ginkgo diterpene lactone meglumine on cognitive function in patients with acute ischemic strokeView study →}

Mechanisms

Pharmacokinetics

Load-bearing, with a nuance. Ginkgolide B is a small, relatively polar trilactone with — for a terpene lactone — reasonable fractional oral absorption, yet only tiny absolute plasma levels: human single-dose studies of oral ginkgo preparations reported GB Cmax of roughly 1–10 ng/mL despite high estimated fractional bioavailability ^{8,9Reference 8Woelkart K et al. · 2010Pharmacokinetics of bilobalide, ginkgolide A and ginkgolide B after three different Ginkgo biloba preparations in humansView study →Reference 9Fourtillan JB et al. · 1995Pharmacokinetic properties of bilobalide and ginkgolides A and B after IV and oral EGb 761 in healthy subjectsView study →}. Elimination is rapid (half-life on the order of a few hours) and predominantly renal, largely as unchanged drug. The GDLM injection deliberately bypasses oral absorption, delivering far higher plasma ginkgolide exposure than any oral dose ^{10Reference 10Wang S et al. · 2016AnimalPharmacokinetics and tissue distribution of ginkgolide A, B and K after IV infusion of ginkgo diterpene lactones in a rat modelView study →} — which is why the clinical efficacy data come from the injectable, not from capsules. The key implication: oral exposures to isolated GB sit roughly two orders of magnitude below its in-vitro antiplatelet IC50, so oral GB’s systemic PAF effect is modest.

Clinical trials

Human trials are for the GDLM injection — a ginkgolide mixture — not purified ginkgolide B, and not the oral isolate: the JAMA Network Open 2023 RCT (~3450 patients, IV GDLM within 48 hours) ^{3Reference 3Zhang Q et al. · 2023RCTEfficacy and safety of ginkgo diterpene lactone meglumine in acute ischemic stroke: a randomised clinical trialView study →}, a smaller GDLM-plus-aspirin RCT ^{4Reference 4Chen C et al. · 2023RCTAntiplatelet effect of ginkgo diterpene lactone meglumine injection in acute ischemic stroke: a randomised controlled trialView study →}, an exploratory cognitive analysis ^{5Reference 5Zhang M et al. · 2024Clinical trialEffectiveness of ginkgo diterpene lactone meglumine on cognitive function in patients with acute ischemic strokeView study →}, and cautiously positive meta-analyses that flag heterogeneity and bias ^{6,7Reference 6Wang L et al. · 2025Meta-analysisGinkgo diterpene lactone meglumine for functional recovery in acute ischemic stroke: a systematic review and meta-analysisView study →Reference 7Zhao H et al. · 2022Meta-analysisThe efficacy and safety of ginkgo terpene-lactone preparations in the treatment of ischemic stroke: a systematic review and meta-analysis of RCTsView study →}. The only human study of the pure molecule is the small 1991 asthma-challenge study of BN52021 ^{13Reference 13Hsieh KH · 1991Effects of the PAF antagonist BN52021 on PAF-, methacholine- and allergen-induced bronchoconstriction in asthmatic childrenView study →} — there are zero RCTs of oral or purified ginkgolide B for any other indication.

Last checked: July 2026.

Toxicity & Safety

Ginkgolide B is one of the better-tolerated ginkgo constituents, and its headline flag — bleeding — is theoretical rather than demonstrated: the concentrations that inhibit platelets in vitro sit roughly 100-fold above what oral dosing achieves in plasma.

Safety at a Glance

✅ Low / no toxicityBleeding risk

• Well tolerated in the trials that exist. GDLM injection RCTs reported adverse-event rates comparable to placebo.
• Not the allergenic or neurotoxic ginkgo compounds. Ginkgolic acids and the seed neurotoxin ginkgotoxin are separate entities.
• Avoid in pregnancy and lactation. No adequate data, and PAF has roles in implantation and parturition.
• Bleeding risk is contested, not established. Inhibitory concentrations are ~100-fold above peak oral plasma levels, and the real-world signal comes from whole-leaf extract case reports.
• Observe additive risk with blood thinners. Anticoagulants, antiplatelets and NSAIDs — especially perioperatively and with the IV injection.
• Theoretical pro-convulsant ceiling. Glycine-receptor blockade at very high exposure, not seen at therapeutic doses.

Full Safety & Interactions Detail

Ginkgolide B is one of the better-tolerated ginkgo constituents — distinct from the allergenic ginkgolic-acid contaminants and the seed neurotoxin ginkgotoxin (both separate entities, not GB) — and GDLM injection RCTs reported adverse-event rates comparable to placebo. The theoretically important flag is bleeding: GB is a PAF antagonist and inhibits PAF-induced platelet aggregation in vitro, but the inhibitory concentrations are roughly 100-fold above peak plasma levels after normal oral dosing, and PAF is a weak platelet agonist unlikely to drive primary hemostasis — so a meaningful hemorrhage risk from oral ginkgolides is contested, with the real-world signal coming chiefly from whole-leaf extract case reports ^{15,2Reference 15Koch E · 2005Inhibition of PAF-induced aggregation of human thrombocytes by ginkgolides: considerations on possible bleeding complications after oral Ginkgo biloba extractsView study →Reference 2Liu Y et al. · 2014Ginkgolide B inhibits platelet release by blocking Syk and p38 MAPK phosphorylation in thrombin-stimulated plateletsView study →}.

Even so, theoretical additive risk with anticoagulants, antiplatelets and NSAIDs is prudent to observe, especially perioperatively and with the IV injection. At the CNS level, GB also acts as a non-competitive blocker of inhibitory glycine (and weakly GABA) receptors ^{11,12Reference 11Kondratskaya EL et al. · 2002BN52021, a platelet-activating-factor antagonist, is a selective blocker of the glycine-gated chloride channelView study →Reference 12Jensen AA et al. · 2007Probing the pharmacophore of ginkgolides as glycine-receptor antagonistsView study →}, giving a theoretical pro-convulsant ceiling at very high exposure that is not seen at therapeutic doses.

Dosage

There is no established oral human dose for purified ginkgolide B, and nothing here is a recommendation. The stroke RCTs used the marketed GDLM injection — a hospital IV drug (roughly 25 mg once daily over about two weeks, per product-defined ginkgolide content), not a supplement and not the isolate ^{3Reference 3Zhang Q et al. · 2023RCTEfficacy and safety of ginkgo diterpene lactone meglumine in acute ischemic stroke: a randomised clinical trialView study →}; the asthma work used administered BN52021 in research settings only ^{13Reference 13Hsieh KH · 1991Effects of the PAF antagonist BN52021 on PAF-, methacholine- and allergen-induced bronchoconstriction in asthmatic childrenView study →}. For exposure reference (not a GB dose), oral EGb 761 at 120–240 mg/day delivers only a milligram-fraction of ginkgolide B, reaching ng/mL plasma levels ^{8Reference 8Woelkart K et al. · 2010Pharmacokinetics of bilobalide, ginkgolide A and ginkgolide B after three different Ginkgo biloba preparations in humansView study →}.

References

1. DeFeudis FV, Drieu K (2000). Ginkgo biloba extract (EGb 761) and CNS functions: basic studies and clinical applications. Current Drug Targets. https://pubmed.ncbi.nlm.nih.gov/11475535/
2. Liu Y, et al. (2014). Ginkgolide B inhibits platelet release by blocking Syk and p38 MAPK phosphorylation in thrombin-stimulated platelets. Thrombosis Research. https://pubmed.ncbi.nlm.nih.gov/25223809/
3. Zhang Q, Wang A, Xu Q, et al. (2023). Efficacy and safety of ginkgo diterpene lactone meglumine in acute ischemic stroke: a randomised clinical trial. JAMA Network Open. https://pubmed.ncbi.nlm.nih.gov/37578791/
4. Chen C, Lv H, Shan L, et al. (2023). Antiplatelet effect of ginkgo diterpene lactone meglumine injection in acute ischemic stroke: a randomised controlled trial. Phytotherapy Research. https://pubmed.ncbi.nlm.nih.gov/36609866/
5. Zhang M, Hu X, Wang T, et al. (2024). Effectiveness of ginkgo diterpene lactone meglumine on cognitive function in patients with acute ischemic stroke. Open Medicine (Warsaw). https://pubmed.ncbi.nlm.nih.gov/38584838/
6. Wang L, Liang X, Chen Y, et al. (2025). Ginkgo diterpene lactone meglumine for functional recovery in acute ischemic stroke: a systematic review and meta-analysis. Journal of Ethnopharmacology. https://pubmed.ncbi.nlm.nih.gov/39880062/
7. Zhao H, Guo Q, Li B, et al. (2022). The efficacy and safety of ginkgo terpene-lactone preparations in the treatment of ischemic stroke: a systematic review and meta-analysis of RCTs. Frontiers in Pharmacology. https://pubmed.ncbi.nlm.nih.gov/35392576/
8. Woelkart K, Feizlmayr E, Dittrich P, et al. (2010). Pharmacokinetics of bilobalide, ginkgolide A and ginkgolide B after three different Ginkgo biloba preparations in humans. Phytotherapy Research. https://pubmed.ncbi.nlm.nih.gov/20041430/
9. Fourtillan JB, Brisson AM, Girault J, et al. (1995). Pharmacokinetic properties of bilobalide and ginkgolides A and B after IV and oral EGb 761 in healthy subjects. Therapie. https://pubmed.ncbi.nlm.nih.gov/7631288/
10. Wang S, Ouyang B, Aa J, et al. (2016). Pharmacokinetics and tissue distribution of ginkgolide A, B and K after IV infusion of ginkgo diterpene lactones in a rat model. Journal of Pharmaceutical and Biomedical Analysis. https://pubmed.ncbi.nlm.nih.gov/27182682/
11. Kondratskaya EL, Lishko PV, Chatterjee SS, et al. (2002). BN52021, a platelet-activating-factor antagonist, is a selective blocker of the glycine-gated chloride channel. Neurochemistry International. https://pubmed.ncbi.nlm.nih.gov/11900860/
12. Jensen AA, Begum N, Vogensen SB, et al. (2007). Probing the pharmacophore of ginkgolides as glycine-receptor antagonists. Journal of Medicinal Chemistry. https://pubmed.ncbi.nlm.nih.gov/17352465/
13. Hsieh KH (1991). Effects of the PAF antagonist BN52021 on PAF-, methacholine- and allergen-induced bronchoconstriction in asthmatic children. Chest. https://pubmed.ncbi.nlm.nih.gov/2009789/
14. Gu JH, Ge JB, Li M, et al. (2012). Inhibition of NF-κB activation is associated with anti-inflammatory and anti-apoptotic effects of ginkgolide B in a mouse model of cerebral ischemia/reperfusion injury. European Journal of Pharmaceutical Sciences. https://pubmed.ncbi.nlm.nih.gov/22850444/
15. Koch E (2005). Inhibition of PAF-induced aggregation of human thrombocytes by ginkgolides: considerations on possible bleeding complications after oral Ginkgo biloba extracts. Phytomedicine. https://pubmed.ncbi.nlm.nih.gov/15693702/
16. Feng Z, Sun Q, Chen W, et al. (2019). The neuroprotective mechanisms of ginkgolides and bilobalide in cerebral ischemic injury: a literature review. Molecular Medicine. https://pubmed.ncbi.nlm.nih.gov/31864312/

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