Ginkgo biloba extract

Mechanism

Apixaban inhibits factor Xa while ginkgo acts on platelet function: bleeding risk adds up at two separate levels of haemostasis. The European monograph places anticoagulants among the treatments that require consultation before taking ginkgo. Unlike warfarin, there is no INR to warn you here: apixaban is not routinely monitored, so the first warning may be the bleed itself.

Symptoms

Gastrointestinal bleeding (black stools, coffee-ground vomit), haematuria, extensive bruising, nosebleeds that do not stop with pressure. Any of these needs urgent attention.

Management

Do not start this combination on your own. Anyone already taking ginkgo with apixaban should raise it at the next appointment; withdrawing the supplement is the first option considered, because the anticoagulant has an indication and ginkgo rarely has one of the same strength. Before surgery or dental extraction, stop ginkgo two weeks ahead.

Mechanism

The European ginkgo monograph notes that concomitant use with anticoagulants increases bleeding risk and that the product should only be taken after consulting a doctor in anticoagulant treatment or bleeding tendency. Ginkgolides inhibit platelet-activating factor, so the effect adds to warfarin at a different step of haemostasis.

Symptoms

Bruises from minimal knocks, gums bleeding when brushing, repeated nosebleeds. Spontaneous intracranial and ocular haemorrhage have been reported with ginkgo. The INR may stay in range, because the platelet pathway does not show up in that measure.

Management

Avoid the combination unless the prescriber has explicitly indicated it. The monograph also advises stopping ginkgo two weeks before planned surgery. If the patient takes it for memory or tinnitus, it helps to know that efficacy in those indications is disputed, while the bleeding risk added to warfarin is concrete.

Mechanism

The European monograph lists antiplatelet drugs alongside anticoagulants among treatments that raise bleeding risk with ginkgo. Aspirin blocks platelet cyclooxygenase irreversibly and ginkgo inhibits platelet-activating factor: two brakes on the same function at different points.

Symptoms

Easy bruising, prolonged bleeding from small wounds, nosebleeds. With antiplatelet-dose aspirin the gastrointestinal risk adds on, which ginkgo neither changes nor offsets.

Management

Declare ginkgo to whoever prescribes the aspirin. The monograph asks for consultation before use in patients on antiplatelets and for stopping it two weeks before surgery. If ginkgo is being taken for memory, weigh the fact that benefit in that indication is not established.

Mechanism

Clopidogrel blocks the P2Y12 receptor and ginkgo inhibits platelet-activating factor. Both act on aggregation through different routes, and the European monograph names antiplatelet agents explicitly among treatments with increased bleeding risk.

Symptoms

Bruising, bleeding gums, prolonged bleeding after minor wounds.

Management

Inform the cardiologist or neurologist who prescribed clopidogrel. If ginkgo is being taken without a firm indication, stopping it is the simple option. On dual antiplatelet therapy after a stent the margin is smaller still, and prior consultation stops being optional.