Ginkgo biloba

Pronunciation: GING-koh bi-LOH-buh.

Generic name: Ginkgo biloba leaf extract
Drug class: Herbal dietary supplement
Form: Standardised leaf extract (oral supplement)
Route: Oral
Legal status: Dietary supplement (not an FDA-approved drug)

Availability and supply rules vary by country

Trade names by country: United States

What Ginkgo biloba leaf extract is and how it works

Ginkgo biloba is a herbal dietary supplement made from the leaves of the Ginkgo biloba tree. It is promoted for various conditions and is not an FDA-approved drug. (1)

Ginkgo leaf extract is used by some people for a range of conditions including anxiety, cognitive issues, and tinnitus, although evidence for many of these uses is inconclusive. It is important to tell your clinician you are taking it, especially because of bleeding risks and interactions with medicines such as warfarin.

Mechanism of action: how Ginkgo biloba leaf extract works

The precise pharmacological mechanism of ginkgo leaf extract is not described in the current research notes, though its potential for increased bleeding risk is highlighted clinically. (1)

What Ginkgo biloba leaf extract is used for

Dementia symptoms

Ginkgo extract may have a modest benefit for dementia symptoms, particularly at relatively high doses, but the overall evidence is described as inconsistent. (1)

Cognitive performance in healthy adults

It is uncertain whether ginkgo influences cognitive performance in healthy people; much of the research on this topic is of low quality. (1)

Anxiety, premenstrual syndrome (PMS), schizophrenia, and vertigo

A small amount of evidence suggests a benefit from taking ginkgo orally for these conditions, but the overall evidence is not conclusive. It might also be helpful in the rehabilitation of patients who have had strokes. (1)

Conditions where ginkgo has NOT been shown to be beneficial

Research indicates ginkgo is not helpful for preventing heart disease, treating high blood pressure, or relieving symptoms of tinnitus or multiple sclerosis. It has also not been shown to prevent or slow the progression of dementia. (1)

Before taking Ginkgo biloba leaf extract

Do not take / not appropriate for

Do not consume fresh or roasted ginkgo seeds or crude ginkgo plant material. Serious side effects have occurred with these forms. Only standardised leaf-extract products are likely to be safe when taken orally in moderate amounts. (all products) (1)

Tell your clinician about

That you are taking ginkgo, especially if you are taking anticoagulant drugs such as warfarin, due to an increased risk of bleeding.
If you are taking any other prescription or over-the-counter medications, as ginkgo may interact with other drugs.
If you are pregnant, as ginkgo may be unsafe and might cause early labor or extra bleeding during delivery if used near that time.
If you are breastfeeding, as little is known about the safety of ginkgo use while breastfeeding.

(1)

How to take Ginkgo biloba leaf extract

Ginkgo leaf extract is taken orally as a dietary supplement.
A specific recommended dose, and specific product-selection guidance, were not established from the sources reviewed for this draft; discuss the appropriate product and dose with a clinician or pharmacist.

(1)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3)

Missed dose

No specific missed-dose guidance was established from the sources reviewed for this draft, since no standard dosing schedule was established either. Ask a clinician or pharmacist what to do if you miss a dose.

Overdose

No specific overdose thresholds or management protocol were established from the sources reviewed for this draft. If you are concerned about the amount taken, or if serious symptoms occur, seek medical attention promptly.

Side effects

Standardised ginkgo leaf extracts are likely to be safe for most adults when taken orally in moderate amounts, and have been used safely in research studies lasting as long as 6 years.

Gastrointestinal symptoms, headache, and dizziness

What to notice: These are the most commonly reported side effects.

What to do: Tell your clinician or pharmacist if these symptoms are severe, persistent, or troublesome. (1)

Increased bleeding risk with anticoagulants

What to notice: A specific patient-facing bleeding-symptom list was not established from the sources reviewed for this draft; do not assume a particular symptom pattern.

What to do: This is especially important if you are also taking an anticoagulant like warfarin. Contact a clinician promptly if you notice anything that concerns you. (1)

Serious warnings

Bleeding risk with anticoagulants — emergency

Symptoms: A specific patient-facing symptom list for major bleeding was not established from the sources reviewed for this draft; do not assume a particular symptom pattern.

Action: Taking ginkgo biloba with warfarin is associated with an increased risk of major bleeding. Seek emergency medical care immediately for anything you believe may be a sign of serious bleeding. Do not stop your prescribed anticoagulant without direct medical advice; let the clinician you see advise on whether continuing or stopping ginkgo is appropriate. (1) (2) (3)

Interactions

Medicine or test	Effect	Action
Anticoagulant drugs (e.g., warfarin)	Ginkgo may increase the risk of bleeding. Taking ginkgo with warfarin is associated with an increased risk of major bleeding events compared with warfarin alone.	Tell your prescriber you are taking ginkgo, or considering it, so they can advise on whether the combination is appropriate for you. (1) (3)
Efavirenz (a non-nucleoside reverse transcriptase inhibitor used for HIV)	Concomitant use of ginkgo biloba preparations and efavirenz is not recommended.	Tell the specialist managing your HIV treatment that you are taking or considering ginkgo. (2)
Other drugs	Ginkgo may also interact with other drugs. The full list of interactions is beyond the scope of the current research notes.	Give your clinician and pharmacist a complete list of all supplements and medicines you are taking. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Ginkgo may be unsafe for use during pregnancy. It might cause early labor or extra bleeding during delivery if used near that time. (1)

Breastfeeding

Little is known about whether it is safe to use ginkgo while breastfeeding. The risks are not established. (1)

Children

No pediatric-specific safety data was found in the sources reviewed for this page. Safety and dosing in children are not established.

Monitoring

Before starting

Tell a clinician you are taking or considering ginkgo, particularly if you are taking anticoagulants such as warfarin.
Surgery/pre-procedure and bleeding-disorder-specific guidance was not established from the sources reviewed for this draft.

During treatment

A specific patient-facing bleeding-symptom list was not established from the sources reviewed for this draft. If you are also taking an anticoagulant like warfarin, tell your clinician anything that concerns you.

(1)

Storage

Specific storage instructions were not established from the sources reviewed for this draft; follow the storage instructions on the product packaging.

Professional information

Clinician-facing context based on limited research notes. This is not a comprehensive clinical guideline.

Regions researched

Indication: General use

Dose summary: No universal standardised dose is established from the sources reviewed. Evidence for a modest benefit on dementia symptoms was noted particularly at 'relatively high doses,' but a specific milligram amount was not extracted from the source text.

Renal context: No renal or hepatic impairment data was found in the sources reviewed for this draft; this remains an evidence gap. (1)

Mechanism of action

Hepatic guidance

No hepatic impairment-specific data was found in the sources reviewed.

Overdose note

No overdose thresholds or specific management protocol were established from the sources reviewed for this draft; this remains an evidence gap. (1)

Frequently asked questions

Can ginkgo biloba prevent dementia?

No. Research has not shown ginkgo to be beneficial for preventing or slowing the progression of dementia. (1)

Is it safe to take ginkgo with my blood thinner?

Taking ginkgo with anticoagulant drugs like warfarin can increase the risk of bleeding, including major bleeding events. Tell your prescriber before combining them — they will advise on whether it is appropriate for you. (1) (3)

Are ginkgo seeds safe to eat?

No. Fresh ginkgo seeds are toxic when consumed orally, and serious side effects have also occurred in people who consumed roasted ginkgo seeds or the crude ginkgo plant. (1)

What is the mechanism of action of Ginkgo biloba leaf extract?