A Dangerous Mix

By Ian K. Smith, M.D.

Doctors have never quite figured out what to say about herbal supplements. While alternative medications have become increasingly popular--Americans will spend some $5 billion this year on natural remedies for everything from arthritis to the common cold--most physicians assumed that even if they didn't know exactly what these remedies did, they were, at worst, harmless. But more and more, doctors are starting to recognize that many natural supplements have medicinal qualities that can complement--or conflict with--the treatments and medications they prescribe.

The American Society of Anesthesiologists is the latest physicians' group to sound a warning about the potential side effects of alternative medications. Concerned by evidence that some supplements can interfere with anesthesia, the group has issued a recommendation that patients stop taking all natural remedies at least two weeks before surgery--giving the body plenty of time to clear them from the system.

The anesthesiologists' warning is based on the latest of several findings that are raising doctors' awareness of the risks associated with natural supplements. Take, for instance, ginkgo biloba, used by almost 11 million Americans to improve memory and increase blood circulation. Doctors now believe ginkgo may reduce the number of platelets in the blood and can prevent blood from clotting properly. Taking ginkgo at the same time one is taking blood-thinning medications, like Coumadin or even aspirin, could make a patient dangerously vulnerable to bleeding.

Similarly, St. John's wort, a popular supplement taken to treat anxiety, depression and sleep disorders, is believed to prolong or increase the effects of some narcotic drugs and anesthetic agents. Ginseng, an herb taken to boost vitality, has been associated with high blood pressure and rapid beating of the heart--conditions that could be deadly in the operating room.

Part of the problem is that herbal supplements and mainstream medicine come from two very different worlds and operate in different regulatory environments. The marketing of prescription and over-the-counter drugs is strictly regulated by the Food and Drug Administration, which requires scientific proof of safety and efficacy. Herbal remedies, by contrast, are largely exempt from FDA supervision. Companies can sell herbal preparations without guaranteeing that what's on the label is inside the bottle.

These uncertainties don't mean that you should never take a supplement. But they make it even more important that you discuss whatever you are taking with your physician--something not enough patients do. A recent study showed that although 60 million Americans have taken alternative medicines, only a third of them reported it to their doctors.

This is a bad idea. A drug your doctor prescribes could be perfectly safe and effective, but if you are taking a similar-acting supplement, there is a real danger of cross-reaction. Don't be afraid to bring your herbal supplements to your doctor's office. Your physician may spot a potential conflict on the label or know of another drug--or even another supplement--that works just as well.

Dr. Ian appears on WNBC-TV in New York City. E-mail him at [email protected] For more on herbals, try altmed.od.NIH.gov