Doctors at the Mayo Clinic have a stern warning for heart patients who take herbal supplements and megavitamins.
They say that popular supplements may interact with prescription medications in ways that increase heart risk for patients.
For instance, St. John's Wort can make blood pressure and cholesterol pills less effective.
Gingko biloba can interact with the blood thinner Coumadin (warfarin) or aspirin to increase the risk for internal bleeding.
Even high doses of garlic have the potential to raise the bleeding risk in those who use anti-clotting drugs.
The Mayo Clinic doctors say too many patients don't tell their doctors when they are taking supplements.
