Cardiovascular effects of ephedra alkaloids: a comprehensive review.

The Ephedra alkaloids have received much press lately secondary to reported adverse events in those using whole extracts as "dietary supplements" for weight loss or athletic performance enhancement. These reports are troubling given the increasing use of these supplements by the general public. We reviewed the available literature as well as online material on these compounds, including information on their pharmacology, regulation, effects on weight loss and athletic performance, and adverse events. Extracts of Ephedra shrubs contain highly active alpha- and beta-adrenergic agonists that have profound effects on the heart and vasculature. Evidence for their effectiveness is limited. Adverse cardiovascular and cerebrovascular effects, including stroke, myocardial infarction, and sudden death, temporally related to their use are well described. The recent Food and Drug Administration ban on these compounds is not broad enough. Ephedra supplements contain a highly bioactive class of compounds that pose a significant risk to the public under the current regulatory framework. More stringent oversight by regulatory authorities is required to minimize the incidence of adverse events.