Herbal supplements and heart medicines may not mix
Many herbal supplements can interact with prescription drugs. Some of these interactions can be life-threatening.
By Mayo Clinic Staff
Herbal supplements are natural, so they must be safe, right? Not necessarily.
Herbal supplements can have strong effects in the body. Some can interact with prescription medications used to treat heart and circulatory problems, such as high blood pressure and heart failure. Some of these interactions can even be dangerous.
About half of U.S. adults report taking supplements. But research suggests that most don't tell their doctors about this use — even those who also take prescription medications.
Yet many herbal supplements may interact with prescription medications, including some used to prevent or treat heart disease.
That's why it's so important to talk with your doctor before taking herbal supplements if you take prescription medications. Your doctor and your pharmacist can help you avoid risky interactions.
Herbal supplements and drug interactions
Several popular herbal supplements interact with common heart medications. This list covers only some interactions. It's important to talk to your doctor before taking any herbal supplements if you take prescription medications.
Coenzyme Q10
Taking coenzyme Q10 can decrease:
- The effectiveness of warfarin (Jantoven)
- Your blood pressure if you also take a calcium channel blocker, such as diltiazem (Cardizem, Tiazac, others)
Danshen
Danshen can interact strongly with certain heart medications, including:
- Anticoagulants. Taking danshen significantly increases your risk of bleeding if you also take warfarin or another anticoagulant, such as clopidogrel (Plavix) or aspirin.
- Calcium channel blockers. Taking danshen increases your risk of low blood pressure if you also take diltiazem or another calcium channel blocker.
- Digoxin (Lanoxin). Taking danshen increases the effects of digoxin — which is used to treat a variety of heart conditions — and puts you at risk of irregular heartbeat (arrhythmia).
Evening primrose
Evening primrose may increase your risk of bleeding if you also take an anticoagulant, such as:
- Aspirin
- Clopidogrel
- Warfarin
Garlic
Garlic increases your risk of bleeding if you also take an anticoagulant, such as:
- Aspirin
- Clopidogrel
- Warfarin
Gingko biloba
Ginkgo biloba increases your risk of bleeding if you also take:
- Aspirin
- Clopidogrel
- Warfarin
Ginseng
Taking ginseng with warfarin decreases warfarin's effectiveness.
Hawthorn
Hawthorn might interact with:
- Beta blockers, such as atenolol (Tenormin), nadolol (Corgard) or propranolol (Inderal, Innopran, Hemangeol)
- Calcium channel blockers, such as diltiazem, nifedipine (Procardia) and verapamil (Calan SR, Verelan)
- Nitrates, such as nitroglycerin (Nitrostat, Nitro-Dur, others) and isosorbide (Dilatrate-SR, Isordil)
- Digoxin
Licorice
Licorice decreases levels of warfarin and can increase the effects of digoxin.
Saw palmetto
Saw palmetto increases your risk of bleeding if you also take:
- Aspirin
- Clopidogrel
- Warfarin
St. John's wort
Taking St. John's wort reduces the effectiveness of:
- Calcium channel blockers
- Digoxin
- Warfarin
- Statins, such as atorvastatin (Lipitor), lovastatin (Altoprev) and simvastatin (Flolipid, Zocor)
Playing it safe with herbal supplements
If your doctor tells you it's OK to use an herbal supplement combined with a medication, make sure you follow dosing instructions carefully. Watch for any signs that you could be having a drug interaction, such as:
- Rapid heartbeat
- Changes in blood pressure
Nov. 14, 2020
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- Liperoti R, et al. Herbal medications in cardiovascular medicine. Journal of the American College of Cardiology. 2017; doi:10.1016/j.jacc.2016.11.078.
- Danshen. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Licorice. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Moore J, et al. Dietary supplement use in the United States: Prevalence, trends, pros, and cons. Nutrition Today. 2020; doi:10.1097/NT.0000000000000402.
- Coenzyme Q-10. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Evening primrose. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Garlic. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Gingko biloba. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Hawthorn. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Saw palmetto. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- St. John's wort. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Nov. 2, 2020.
- Sirois FM, et al. Use and disclosure of complementary health approaches in U.S. adults with cardiovascular disease. American Journal of Cardiology. 2018; doi:10.1016/j.amjcard.2018.03.014.