What supplements should I avoid when taking apixaban?

According to a 2019 study, one-fifth of patients on direct-acting oral anticoagulants like apixaban were taking dietary supplements with potentially serious interactions. Knowing what supplements should I avoid when taking apixaban is crucial for preventing dangerous side effects, such as an increased risk of bleeding or reduced medication effectiveness.

Quick Summary

Identify supplements and certain foods to avoid when on apixaban (Eliquis) therapy due to the risk of either dangerous bleeding or compromised medication efficacy. It is critical to discuss all supplements with a healthcare provider to ensure safety and effectiveness.

Key Points

• Consult a Doctor: Always discuss all supplements, herbs, and over-the-counter medications with your healthcare provider before starting or stopping anything while on apixaban.

• Avoid St. John's Wort: This herb significantly reduces the effectiveness of apixaban, which can put you at a higher risk for blood clots.

• Limit Blood-Thinning Supplements: Herbs like ginkgo biloba, garlic, and turmeric can increase the risk of bleeding when combined with apixaban.

• Be Cautious with High-Dose Fish Oil: Large amounts of Omega-3 fatty acid supplements can heighten bleeding risk. Discuss your dosage with a doctor.

• Avoid Grapefruit: Large quantities of grapefruit or its juice can dangerously increase apixaban levels in your blood, raising the risk of serious bleeding.

• Watch for Signs of Bleeding: Be vigilant for unusual bruising, nosebleeds, red/black stools, or other signs of bleeding and contact your doctor immediately if they occur.

Apixaban, commonly known by the brand name Eliquis, is a powerful anticoagulant prescribed to prevent blood clots. While it offers a simpler regimen than older anticoagulants like warfarin, it is not free from interactions. Many over-the-counter (OTC) supplements, herbs, and even some common foods can interfere with apixaban's mechanism, altering its effectiveness or dangerously increasing the risk of bleeding. Patients often mistakenly assume that natural products are benign, but this is a serious and potentially life-threatening misconception.

Supplements That Increase Bleeding Risk

Some supplements have antiplatelet or anticoagulant properties, meaning they can thin the blood. Combining these with apixaban, which also prevents blood clotting, can have a cumulative effect that significantly increases your risk of bleeding or bruising.

• Ginkgo Biloba: This popular herbal supplement is known for its blood-thinning properties. Taken with apixaban, it can heighten the risk of bleeding, particularly internal bleeding.
• Omega-3 Fatty Acids (Fish Oil): High doses of fish oil supplements, particularly exceeding 3 grams per day, can increase the risk of bleeding. While lower doses are generally considered less risky, it's essential to discuss any dosage with your doctor.
• Garlic: High-dose garlic supplements have antiplatelet properties and can increase the risk of bleeding when used with apixaban. While small, dietary amounts are unlikely to be an issue, concentrated forms should be avoided.
• Vitamin E: High doses of vitamin E supplements can have anticoagulant effects, raising the risk of bleeding when combined with apixaban.
• Turmeric (Curcumin): The active component of turmeric, curcumin, has antiplatelet properties. High-dose turmeric supplements should be avoided with apixaban due to the risk of increased bleeding.
• Ginger: Ginger has antiplatelet effects, and high intake from supplements or large amounts of tea can increase bleeding risk. There are case reports linking excessive ginger consumption with bleeding episodes in patients on similar anticoagulants.

Supplements That Reduce Apixaban's Effectiveness

Certain supplements can decrease the concentration of apixaban in your bloodstream by influencing its metabolism in the liver. This can make the medication less effective, increasing your risk of developing blood clots.

• St. John's Wort: This herbal remedy, often used for depression, is a potent inducer of the CYP3A4 enzyme and P-glycoprotein efflux transporter. This accelerates the metabolism of apixaban, leading to lower blood levels and a reduced therapeutic effect, which can increase the risk of a stroke or blood clot. It is crucial to avoid St. John's wort completely when taking apixaban.
• High-Dose Green Tea Extract: While regular dietary consumption of green tea is generally fine, high-dose supplements or extracts containing vitamin K can potentially reduce apixaban's effectiveness.

Other Important Considerations

Beyond supplements, some dietary items can also cause significant interactions.

• Grapefruit and Grapefruit Juice: Grapefruit and its juice inhibit the CYP3A4 enzyme, the same enzyme mentioned with St. John's wort, but with the opposite effect. This can prevent apixaban from being properly metabolized, leading to dangerously high levels of the drug in your system and a greater risk of bleeding. You should avoid large amounts of grapefruit products.
• Cranberry Supplements: Concentrated cranberry supplements may interact with apixaban by inhibiting CYP3A4, potentially increasing the risk of bleeding. Unlike warfarin, apixaban's interaction is not with vitamin K but with the enzyme pathway.

Supplement Interaction Comparison Table

Supplement	Potential Interaction	Mechanism/Reason	Precaution Level	Source(s)
St. John's Wort	Reduces apixaban effectiveness	Induces CYP3A4 and P-glycoprotein, increasing metabolism	AVOID
Ginkgo Biloba	Increases bleeding risk	Has antiplatelet properties	AVOID (especially supplements)
High-Dose Fish Oil	Increases bleeding risk	Enhances anticoagulation effects (antiplatelet)	CAUTION (consult doctor)
High-Dose Vitamin E	Increases bleeding risk	Has anticoagulant-like effects	CAUTION (consult doctor)
Turmeric (Curcumin) Supplements	Increases bleeding risk	Curcumin has antiplatelet properties	AVOID (concentrated forms)
Grapefruit & Juice	Increases bleeding risk	Inhibits CYP3A4, increasing apixaban levels	AVOID (large amounts)

Conclusion

While apixaban generally has fewer dietary restrictions than older blood thinners like warfarin, it is critical to be cautious with OTC supplements, herbs, and concentrated foods. The potential for harmful interactions is significant and should not be underestimated. Always inform your healthcare provider about all prescription medications, OTC products, and supplements you are taking or plan to take. They can help you make informed decisions and monitor for any potential adverse effects. For reliable information on your medication, you can also consult resources like the MedlinePlus Drug Information for Apixaban.

Frequently Asked Questions

Frequently Asked Questions

Is it safe to take a multivitamin while on apixaban?

Yes, a standard multivitamin is typically safe with apixaban. Unlike warfarin, apixaban's effect is not significantly altered by dietary vitamin K. However, avoid high-dose single vitamins, especially high-dose Vitamin E, and always consult your doctor before starting any new supplement.

What if I use a small amount of ginger or turmeric in my cooking?

Normal dietary amounts of ginger and turmeric are unlikely to cause a significant interaction with apixaban. The risk is associated with concentrated supplements or large, excessive consumption, not standard cooking use.

Can I have grapefruit if I'm taking apixaban?

It is best to avoid large quantities of grapefruit and grapefruit juice. While a small amount is likely fine, large amounts can block the enzyme that metabolizes apixaban, leading to higher levels of the drug in your body and a greater risk of bleeding.

What are the signs of a dangerous interaction with supplements?

Signs of a dangerous interaction include unusual or easy bruising, nosebleeds, blood in your urine or stool, bleeding gums, severe headache, dizziness, or weakness. You should seek immediate medical attention if you experience these symptoms.

Does this apply to concentrated green tea supplements?

Yes, while moderate amounts of green tea as a beverage are safe, high-dose green tea extracts or supplements contain a more concentrated amount of compounds that could affect apixaban and increase bleeding risk.

Why do some supplements cause increased bleeding?

Some supplements, like ginkgo biloba and high-dose fish oil, have antiplatelet properties, meaning they can prevent blood platelets from clumping together. When combined with apixaban, which also prevents clotting, this effect is compounded, leading to a higher risk of uncontrolled bleeding.

Why is St. John's Wort so dangerous with apixaban?

St. John's wort reduces apixaban's effectiveness by speeding up the liver's metabolism of the drug through a specific enzyme pathway (CYP3A4). This means there is less apixaban circulating in your blood to prevent blood clots, increasing your risk of a stroke or other serious thrombotic event.