Herbal remedies like ginkgo biloba and St. John’s wort have grown in popularity in recent years as natural treatments for everything from fatigue and depression to headache and anxiety. Yet, according to a review article published in the February 9 issue of the Journal of the American College of Cardiology, for patients taking certain heart medications, these centuries-old herbal remedies can introduce some dangerous modern complications. For example, heart patients on an aspirin regime or who take the blood thinner Warfarin (also known as Coumadin) may be at higher risk for bleeding if they combine those medications with ginkgo biloba. And St. John’s wort, popularly used to treat sleep problems or depression, can interact with heart medications to increase the risk for arrhythmias, high blood pressure and high levels of cholesterol.
While these herbal treatments can have very real impact on the effectiveness of heart medications, because they are over-the-counter “natural” remedies, doctors don’t always remember to inquire about them, and patients often leave them off the list of medications they are taking. It’s this information gap that Dr. Arshad Jahangir, a cardiologist with the Mayo Clinic and an author of the review, hope to close. Jahangir suggests that misconceptions about the very real effects of so-called “natural” remedies may give people a false sense of security—one that can be particularly dangerous for elderly heart patients, who are more likely to have co-existing conditions and are already at higher risk for bleeding.
Promoting greater awareness of these potential interactions, and encouraging both health care providers and patients to compile more complete pictures of their medication regimes is key, the authors argue. Yet, so too is ensuring that doctors and medical staff know which questions to ask. Some supplements—garlic and grapefruit juice, for example—may simply seem like parts of a healthy diet, but in certain amounts can interact dangerously with heart medications. Garlic supplements, often taken to help lower blood pressure and improve overall immune system health, can increase the risk for bleeding among patients taking Warfarin, for example.
The authors don’t dismiss the potential merits of herbal remedies, many of which have been used for centuries, but they do point to a need for greater education—and scrutiny. Because most herbal remedies are classified as food products, they aren’t put through the trials and analysis that are standard for other medications.
To learn more about potential problems with herbal supplements you may be taking, check out these fact sheets from the American Academy of Family Physicians about side effects (PDF) and interactions with other medications (PDF), or this information from the Mayo Clinic.