March 30, 2000 (Eugene, Ore.) -- An extract of the herb ginkgo biloba seems to be just as useful as conventional medications in treating leg cramps caused by a lack of oxygen from an inadequate blood supply (claudication), a new study says. But patients who start getting regular physical exercise have shown even greater improvements in their ability to walk without pain.
Claudication occurs because of blockages in the arteries that supply blood, oxygen and nutrients to the legs. The condition arises from the same causes as heart disease, such as high blood pressure, diabetes, and high cholesterol. When someone with claudication tries to walk, the muscles in the legs are starved for oxygen, and thus become painful. Resting usually makes the pain go away.
"The beneficial effect from this herbal extract is robust and reproducible," says study author Edzard Ernst, MD, PhD, whose work is published in this month's issue of The American Journal of Medicine. "The [effect] of ginkgo is modest, but so is the [effect] of any medication for this condition." Ernst is a professor of complementary medicine at the school of postgraduate medicine and health sciences at the University of Exeter in England.
"This thoughtful paper compares ginkgo treatment to other treatments for claudication," says James Dillard, MD, DC, CAc, who was not involved in the study. "Looking at those numbers, we see the effect of ginkgo is in the same ballpark as the pharmaceuticals in current use" while the side effects appear to be less, he says. Dillard, who is board-certified in physical medicine and rehabilitation, is medical director for alternative medicine at Oxford Health Plans and author of Alternative Medicine for Dummies.
People who have this sort of intermittent cramping in their legs often have heart disease, so patients who are thinking about using ginkgo for leg cramps should talk with their physicians first, Dillard warns. "You shouldn't use biologically active herbal extracts to treat medical illness without consulting a physician. Combining ginkgo with other medications such as aspirin or blood thinners could be a recipe for disaster; it might lead to [severe] bleeding. Blood thinning is not for amateurs."
"Ginkgo is definitely useful for claudication, but it is one herb you should only take after advice from your physician," agrees Mary Hardy, MD. Hardy says that five years ago, most doctors were not aware of ginkgo or other herbs. Today, she says, about half of them are. "Physicians are more interested in these issues today and have educated themselves about them. If your doctor is not familiar with ginkgo biloba, they can now go to their medical library and review the published data about it." Hardy, a board-certified internal medicine physician with special training in herbal medicines, is medical director of the integrative medicine medical group at Cedars-Sinai Medical Center in Los Angeles.
One problem for consumers is that there are so many different ginkgo preparations, says Ernst. "In an American health food store you find two dozen different items, and no guidance in choosing among them. I would recommend the two products which were used in the formal clinical trials on ginkgo; they are made by Schwabe and Lichtwer."
Hardy adds that "EGb 761," the ginkgo extract made by Schwabe, has been licensed to several U.S. manufacturers and should be available. "We don't know if other preparations are equivalent," he says.
Even though ginkgo was found to have a modest effect, the authors of the study write that "the increase in pain-free walking distance with regular physical exercise is substantially greater than for medications." While the new study showed an improvement in pain-free walking distance of about 33 meters (about 108 feet), a previous study found a gain of 139 meters (about 456 feet) with exercise training.
Steven Horowitz, MD, says that line in the study caught his attention. "In my own experience, once people with claudication get into the habit of regular exercise, many of them become symptom-free. This article should have concluded by saying we still don't have anything nearly as good as exercise, so we need to focus our attention on that." Horowitz, who reviewed the study for WebMD, is chief of medical cardiology at Beth Israel Medical Center and professor of medicine and nuclear medicine at the Albert Einstein College of Medicine in New York.
Ernst agrees that exercise and stopping smoking are of prime importance in treating the condition. "There is no question that recommendations for exercise should come before any medication, herbal or otherwise. However, the problem with exercise is that people don't do it."
People who aren't used to exercise often find it hard to form new habits, Ernst says, especially for patients with claudication, since exercise can be painful. "Even though exercise may be painful, it is still [helpful]. Asking the muscles to function on limited oxygen will stimulate the new growth of blood vessels." Once formed, these new vessels may then be able to handle the needs of the muscles without drugs or herbs.
- Claudication is painful cramping in the legs caused by blockages in the arteries, which limit oxygen supply to the muscles.
- A new study shows that an extract of the herb ginkgo biloba modestly improves the distance that people with claudication can walk without pain.
- Exercise, however, works far better than either ginkgo or drugs, and many patients who begin a regular exercise program become symptom free.