Weight-loss pill carries risks. (Biomedicine).

An analysis of past research on ephedra, an over-the-counter dietary supplement, indicates that the pill leads to modest weight loss but poses significant dangers to health. Those include psychiatric problems and a wide range of physical harm, such as damage to the heart and stomach. The analysis also suggests that ephedra doesn't enhance athletic performance, says Paul G. Shekelle of the Southern California Evidence-based Practice Center-RAND in Santa Monica, Calif.

The studies indicate that ephedra use should be restricted, says Shekelle, who conducted the analysis with several colleagues. "The existing evidence about harm is strong enough to say it outweighs any chance of benefit," he says. The Food and Drug Administration is currently reviewing the study, which appears in the March 26 Journal of the American Medical Association (JAMA). The Department of Health and Human Services commissioned Shekelle and his colleagues to examine the scientific literature on ephedra and ephedrine, the chemical presumed to be the herbal supplement's active ingredient.

The analysts reviewed 20 studies that gauged the effectiveness of ephedra or products containing ephedrine. The collective message of the studies is that the supplement multiplies various health risks 2.2- to 3.6-fold. Specific problems include depression, anxiety, insomnia, sweating, vomiting, heartburn, nausea, and heartbeat irregularities.

The scientists also found 15,951 cases in which either a doctor or a user of ephedra or ephedrine reported a medical problem to a manufacturer or the FDA. Of these, 283 were severe, including 5 deaths, 5 heart attacks, 4 seizures, 11 strokes, and 8 psychiatric disturbances.

Shekelle and his colleagues have provided "the best scientific evidence yet" that ephedra poses health risks, says physician Phil B. Fontanarosa, executive deputy editor of JAMA.--N.S.