Authors' objectives:

This report aims to assess the efficacy of herbal ephedra-containing dietary supplements and ephedrine on weight loss and athletic performance, through comprehensive literature review and synthesis of evidence. We also assessed safety of these products through review of adverse events reported in clinical trials, published case reports of adverse events, reports on file with the U.S. Food and Drug Administration (FDA), and a file of reports kept by a manufacturer of ephedra products, Metabolife.

Authors' results and conclusions: Weight Loss: Short-term use of ephedrine, ephedrine plus caffeine, or dietary supplements containing ephedra with or without herbs containing caffeine is associated with a statistically significant increase in short-term weight loss (compared to placebo). The addition of caffeine to ephedrine is associated with a statistically significant modest increase in short-term weight loss. The observed effects on weight loss of ephedrine plus caffeine and ephedra-containing dietary supplements with or without herbs containing caffeine are approximately equivalent: a weight loss approximately two pounds per month greater than that with placebo, for up to four to six months. No studies have assessed the long-term effects of ephedrine or ephedra-containing dietary supplements on weight loss; the longest published treatment duration was six months. Athletic Performance: The effect of herbal ephedra-containing dietary supplements on athletic performance has not been assessed. The few studies that assess the effect of ephedrine on athletic performance have included only small samples of fit individuals (young male military recruits) and have assessed its effect only on very short-term immediate performance. These data support a modest effect of ephedrine plus caffeine on very short-term athletic performance. One study reported the addition of caffeine to ephedrine is necessary to produce an effect on athletic performance. No studies have assessed the sustained use of ephedrine on performance over time. Safety Issues: There is sufficient evidence from controlled trials to conclude that the use of ephedrine and/ or the use of ephedra-containing herbal supplements or ephedrine plus caffeine is associated with two to three times the risk of nausea, vomiting, psychiatric symptoms such as anxiety and change in mood, autonomic hyperactivity, and palpitations. The controlled trials studied relatively few people and in aggregate were insufficient to evaluate events with a risk of less than 1.0 per one thousand. The majority of case reports are insufficiently documented to make an informed judgment about a relationship between the use of ephedrine or ephedra-containing dietary supplements and the adverse event in question. Prior ephedra consumption was associated with two deaths, three myocardial infarctions, nine cerebrovascular accidents, three seizures, and five psychiatric cases as sentinel events. Prior consumption of ephedrine was associated with three deaths, two myocardial infarctions, two cerebrovascular accidents, one seizure, and three psychiatric cases as sentinel events. We identified 43 additional cases as possible sentinel events with prior ephedra consumption and seven additional cases as possible sentinel events with prior ephedrine consumption. About half the sentinel events occurred in persons aged 30 years or younger.

Authors' recommendations: Ephedrine, ephedrine plus caffeine, and ephedra-containing dietary supplements with or without herbs containing caffeine all promote modest amounts of weight loss over the short term. There are no data regarding long-term effects on weight loss. Single-dose ephedrine plus caffeine has a modest effect on athletic performance. The available trials do not provide any evidence about ephedrine or ephedra-containing dietary supplements, as they are used by the general population, to enhance athletic performance. Use of ephedra or ephedrine plus caffeine is associated with an increased risk of gastrointestinal, psychiatric, and autonomic symptoms. The adverse event reports contain a sufficient number of cases of death, myocardial infarction, cerebrovascular accident, seizure, or serious psychiatric illness in young adults to warrant a hypothesis-testing study, such as a case-control study, to support or refute the hypothesis that consumption of ephedra or ephedrine may be causally related to these serious adverse events.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.ahrq.gov/downloads/pub/evidence/pdf/ephedra/ephedra.pdf

Year Published: 2003

URL for published report: http://www.ahrq.gov/clinic/tp/ephedtp.htm

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: United States

Organisation Name: Agency for Healthcare Research and Quality

Contact Address: Center for Outcomes and Evidence Technology Assessment Program, 540 Gaither Road, Rockville, MD 20850, USA. Tel: +1 301 427 1610; Fax: +1 301 427 1639;

Contact Name: martin.erlichman@ahrq.hhs.gov

Contact Email: martin.erlichman@ahrq.hhs.gov

Copyright: Agency for Healthcare Research and Quality (AHRQ)