A new study highlights potentially dangerous interactions between herbal supplements and prescription medications. Researchers looked at dozens of reports of serious drug interactions among patients with disorders like high-blood pressure, diabetes, cancer and depression. They found herbal supplements may affect medications' effectiveness or have side effects.
"For most Americans who are about to take their ginko biloba… they're thinking that it's to enhance their health. They're thinking it's natural, it must be safe. They're not thinking about risk," CBS News medical contributor Dr. Tara Narula said Wednesday on "CBS This Morning." "But the fact of the matter is that herbal supplements are pharmacologically active. They're biologically active."
They can change your blood sugar, blood pressure or cholesterol, for example, Narula said. Not only can the supplements work for or against the condition you're treating, but they can also impact your metabolism and alter the amount of drug in your system, she explained.
"To give you an example, if you're a cardiac patient and you're taking a blood thinner like coumadin, and then you're taking a specific herbal supplement, that could either make the coumadin levels higher or lower in your system, which means you'd be maybe more likely to bleed or that you may be more likely to clot," Narula said. "If you're taking a statin, you may be more likely to have muscle aches or pains. If you're a cancer patient on chemotherapy, it may not be as effective, the chemotherapy. If you're on anti-depressants, it may make you more depressed."
More than half of Americans say they take dietary and herbal supplements, including gingko biloba, ginseng or St. John's Wort. Up to one in four adults report taking supplements and prescription drugs at the same time. Many don't ask their doctor if it's safe, which is a big issue, Narula said.
"Ninety percent of the people I ask, they tell me that they are taking some form of a supplement. But it's only when I ask," Narula said. "Whether it's because they don't think that it's important or they don't want the doctor to tell them don't take that, I'm not sure. But the reality is, it's important because you need that open dialogue to discuss the pros and cons."
She said there is no data or science to support health benefits to herbal supplements.
"In this country, we don't get educated in the medical profession about it. But no doubt that there are probably some benefits, but you have to weigh them with the risks," Narula said.