Serious Side Effects Of Ginkgo Biloba: Risks, Warnings, And Safety Guide

Unexpected interactions with common medications can turn herbal remedies into hazards.

By Medha deb

Created on Sep 18, 2025

Unexpected interactions with common medications can turn herbal remedies into hazards.

Ginkgo biloba, hailed for its potential to enhance memory and cognitive function, is one of the world’s oldest living tree species. Its leaves have been used for centuries in traditional medicine, and today, extracts are consumed globally as dietary supplements. While ginkgo is generally well-tolerated, it can cause a range of side effects—some mild, others potentially life-threatening. Understanding these risks is essential for safe use.

What Is Ginkgo Biloba?

Ginkgo biloba is a herbal supplement derived from the leaves of the ginkgo tree. It is most commonly promoted for cognitive enhancement and circulation improvement. Typically available as capsules, tablets, teas, or extracts, ginkgo is often self-prescribed for age-related memory problems, anxiety, and other conditions. Its active constituents, including flavonoids and terpenoids, are believed responsible for its effects but can also contribute to adverse reactions.

Common Side Effects Of Ginkgo Biloba

Most users experience no serious issues, but some mild side effects are relatively common. These often resolve after discontinuation but should be monitored.

Stomach upset: Nausea, vomiting, stomach pain, and dry mouth sometimes occur when starting ginkgo biloba supplements.
Diarrhea or constipation: Gastrointestinal disturbances—either loose stools or difficulty passing stools—can happen in some individuals.
Headache and dizziness: Ginkgo may trigger frequent headaches or feelings of light-headedness, and in rare cases, sleep problems (insomnia).
Allergic reactions: Allergic rashes and skin itching may result from oral or topical contact, especially in individuals sensitive to alkylphenols.

Though these effects are typically mild, persistent symptoms should prompt consultation with a healthcare professional.

Serious And Potentially Life-Threatening Side Effects

In rare cases, ginkgo biloba may cause more severe adverse events that require immediate medical attention.

Increased Risk Of Bleeding

Ginkgo biloba significantly increases bleeding tendency, particularly among those using blood-thinning medications or with bleeding disorders. Major concerns include:

Easy bruising
Frequent nosebleeds
Abnormal gum bleeding
Unusual vaginal bleeding
Blood in urine or stool
Coughing or vomiting blood
Persistent or expanding bruises
Severe or sudden headaches

Ginkgo can interact dangerously with anticoagulants like warfarin, aspirin, and NSAIDs (ibuprofen, naproxen), dramatically increasing the risk of internal and external bleeding. Individuals on these medications should avoid ginkgo unless cleared by their provider.

Raised Risk Of Seizures

Consumption of high doses of ginkgo—particularly supplements contaminated with ginkgo seeds—can raise the likelihood of seizures due to neurotoxic compounds present in seeds. Key points:

Ginkgo may reduce blood levels of certain anti-seizure medications, making seizures more likely.
Individuals with a history of seizures, epilepsy, or those on anti-convulsant therapy should avoid ginkgo supplementation.
If a seizure occurs while using ginkgo, seek emergency medical care immediately.

Heart Palpitations And Arrhythmia

Some users report heart palpitations—rapid, pounding, or irregular heartbeats—as well as arrhythmias (irregular heart rhythms). These effects may be more pronounced in those with existing cardiovascular conditions. Symptoms to watch for include:

Fast, slow, or uneven heart rate
Weak, shallow breathing
Loss of consciousness
Chest pain or severe dizziness

Heart-related adverse events should be evaluated promptly by a healthcare practitioner.

Allergic And Skin Reactions

Contact or ingestion can lead to skin problems ranging from mild itchy rashes to severe reactions such as:

Hives, swelling of face or throat
Blistering, peeling skin
Red or purple skin rash
Fever, sore throat, burning eyes (severe allergic reaction)

Immediate discontinuation and medical evaluation are necessary if any severe cutaneous reaction occurs.

Drug Interactions To Watch Out For

Ginkgo biloba can interact with a wide variety of prescription and nonprescription drugs. Notable interactions include:

Blood thinners (anticoagulants) such as warfarin and aspirin—raise bleeding risk markedly.
NSAIDs (ibuprofen, naproxen)—synergistic bleeding risk.
Antidepressants (SSRIs, MAOIs)—may increase side effects or alter effectiveness.
Anti-seizure medications—reduce effectiveness, increasing seizure risk.

Always discuss ginkgo use with your healthcare provider or pharmacist before combining with any medications or supplements.

Who Should Avoid Ginkgo Biloba?

Certain populations are at higher risk for adverse outcomes and should generally avoid ginkgo biloba supplements:

People with bleeding disorders or on blood-thinning medications
Individuals with a history of seizures or taking anti-epileptic drugs
Those prone to allergic reactions, especially to alkylphenols
Pregnant and breastfeeding women (insufficient safety data)
Children, due to unknown effects on the developing nervous system

If unsure, consult a healthcare provider before starting ginkgo biloba therapy.

Safe Use Guidelines For Ginkgo Biloba

Adhering to responsible usage practices reduces the risk of serious side effects.

Only purchase trusted brands with clear dosage labeling and third-party testing.
Begin with the lowest effective dose, increasing only as advised by a healthcare professional.
Regularly review all other medications and supplements in use with your provider.
Monitor for new or worsening symptoms during use. Discontinue immediately and seek care for major reactions.
Avoid combining ginkgo with substances known to increase bleeding or seizure risk.

When Should You Contact Your Healthcare Provider?

Promptly report any new symptoms or side effects—especially those listed below:

Signs of severe allergic reaction: hives, difficulty breathing, facial swelling
Persistent headache, dizziness, nausea, or sleep disturbances
Unusual bruising or bleeding that does not stop
Seizures or abnormal heart rhythm

In emergency situations, bring the ginkgo biloba product used to aid diagnosis and management.

Table: Common Vs. Serious Side Effects Of Ginkgo Biloba

Side Effect Type	Examples	Severity	Recommended Action
Common (Mild)	Upset stomach, headache, dizziness, diarrhea, constipation, mild skin rash	Usually mild	Monitor; discontinue if persistent
Serious (Severe)	Abnormal bleeding, seizures, severe allergic reaction, heart rhythm disturbances	Life-threatening	Discontinue; seek immediate medical attention

Frequently Asked Questions (FAQs) About Ginkgo Biloba Side Effects

Q: Can ginkgo biloba cause allergic reactions?

A: Yes. Both oral supplements and skin contact with the ginkgo plant can trigger mild to severe allergic reactions in sensitive individuals. Symptoms include rashes, hives, swelling, and severe skin disorders.

Q: Is ginkgo biloba safe for people taking blood thinners?

A: No. Ginkgo biloba can significantly increase bleeding risk for individuals taking medications such as warfarin, aspirin, or NSAIDs. This combination should only be considered under direct medical supervision.

Q: Can ginkgo biloba cause seizures?

A: There is a risk, especially at high doses or with supplements contaminated by seeds. Individuals with a history of seizures or who are taking anti-epileptic drugs should avoid ginkgo biloba.

Q: What should I do if I experience severe side effects?

A: Discontinue the supplement immediately and seek urgent medical care, especially for signs of severe allergic reaction, uncontrolled bleeding, seizure, or heart issues. Take the supplement container with you.

Q: Does ginkgo interact with antidepressants or painkillers?

A: Yes. Ginkgo can interact with SSRIs, MAOIs, and NSAIDs, potentially increasing side effect risk or altering drug effectiveness. Consult a physician before using ginkgo with these medications.

Expert Tips For Choosing And Using Ginkgo Biloba Supplements

Only use standardized extracts from reputable brands with quality control certification.
Check labeling for the absence of seeds or crude plant materials, which may increase toxicity.
Monitor for dose-dependent side effects—never exceed recommended amounts.

References

National Center for Complementary and Integrative Health. “Gingko.”
Bent, S., et al. (2005). Spontaneous bleeding associated with ginkgo biloba. Journal of General Internal Medicine.
Mei, N., et al. (2017). Review of ginkgo biloba-induced toxicity, from experimental studies to human case reports. Journal of Environmental Science and Health.
GoodRx. 8 Common Side Effects of Ginkgo Biloba to Know Before Taking It.
Drugs.com. Ginkgo Biloba Side Effects: Common, Severe, Long Term.
Healthline. Ginkgo biloba possible benefits and risks.
WebMD. Ginkgo – Uses, Side Effects, And More.

Key Takeaway

Ginkgo biloba remains a widely used herbal supplement but presents important risks—especially for vulnerable groups. Know your personal risk factors, track symptoms closely, and always consult a healthcare professional before starting or continuing ginkgo biloba supplementation.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

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