In a report in today's Journal of the American Medical Association, researchers warn that commonly used herbal medications may cause serious problems in patients during surgery and that more doctors need to know what herbal medications their patients are taking before the operation.
"Many of these herbs can interfere with bodily functions and can cause complications, even death," says University of Chicago researcher Jonathan Moss, one of the study's authors.
The study, a review of 35 years of published research, shows how: gingko biloba, ginseng and garlic, which thin the blood, may cause internal bleeding during and after surgery; ephedra, often used for weight loss, may disrupt heart rate and blood pressure during an operation; kava and valerian, taken as tranquilizers, may prolong the effects of anesthesia; St. John's wort, used as an antidepressant, may weaken the effects of surgical drugs.
An estimated 60 million Americans use some form of herbal remedy. Most of these are common supplements sold at ordinary health food stores across the country. Few people, however, realize the harm these extracts may cause during surgery.
Making matters worse, 70 percent of patients never tell their doctors before an operation what herbal supplements they're taking, and many doctors are not asking.
Amazingly, the study says many doctors are still unaware of the potential risks.
"We traditionally haven't been trained in herbal medication," explains Moss. "We come to this by virtue of the fact our patients often take them."
To reduce the risks, many doctors suggest patients stop taking herbal supplements two weeks before surgery. However, this advice is of little help to patients undergoing emergency operations.