Clinical Study on Ephedra and Ephedrine for Weight Loss and Athletic Performance

Obectives: Look into the effectiveness of herbal dietary supplements that contain ephedra and/or ephedrine on weight loss and athletic performance. This was done by a comprehensive review of literature and synthesis of evidence. The safety of using the products was also looked into. This was done by reviewing adverse events reported in clinical trials, published case reports, reports filed with the U.S. FDA, and consumer complaints received by an ephedra product manufacturer.

Search Strategy: Several electronic databases were searched to find studies involving herbal ephedra and ephedrine. This included MEDLINE®, EmBase, BIOSIS, Allied® Complementary Medicine Database, the Cochrane Controlled Clinical Trials Register Database, International Pharmaceutical Abstracts, Pascal, and SciSearch. Unpublished studies were also obtained through posting notices in related journals and contacts on the Techincal Expert Panel. Adverse event reports were received from the FDA and a manufacturer of ephedra products.

Selection Criteria: Weight loss studies were only looked at for efficacy if they were controlled trials with human subjects that were at least eight weeks in length. Athletic performance studies were accepted as long as they were controlled trials with human subjects. All adverse events reports found/provided were assessed including ones from clinical trials that were too short to be included for efficacy.

Data Collection and Analysis: There were 59 articles related to 52 controlled clinical trials of ephedrine or herbal ephedra usage for weight loss or athletic performance looked at. Forty-four of these studied weight loss effects. Eighteen of these were excluded due to them being less than eight-week trials. An additional thirteen related to 6 trials were excluded for various reasons.

The weight loss effects of ephedra and ephedrine use were looked at in six different comparisons: ephedrine vs. placebo, ephedrine with caffeine vs. placebo, ephedrine with caffeine vs. ephedrine, ephedrine vs. other active treatment, ephedra vs. placebo, and ephedra with herbs containing caffeine vs. placebo.

There were only 4 placebo-controlled trials in the ephedra with herbs containing caffeine category and 1 in the ephedra without herbs containing caffeine category for athletic performance usage. Due to the small numbers, the eight athletic performance trials were compared and contrasted as a narrative review instead of synthesized statistically. Pooled meta-analysis was done of adverse event symptoms that frequently occurred in controlled trials.

When the individual adverse event reports were looked at, the fact that an adverse event occurred was looked for as well as documentation that the affected used ephedra within 24 hours before the adverse event or the toxicological examination showed ephedrine or related product in the blood or urine. The reports were also searched through for documentation that other possible causes were looked at and excluded. Those that met all this criteria were categorized as sentinel/unanticipated events. Cases that met all, but the possible causes were not excluded in the documentation were categorized as possible sentinel events. Being categorized as a sentinel event does not mean a proven cause-and-effect relationship. Clinical judgment of expert clinicians was used to determine if other causes were sufficiently looked at and excluded.

Main Results:

Weight Loss – The efficacy of ephedrine, ephedrine plus caffeine, or dietary supplements with ephedra with or without caffeine herbs has been shown to improve short-term weight loss significantly more than the placebo groups. Using ephedrine with caffeine provided a moderate increase in short-term weight loss. Ephedra with or without caffeine herbs had about the same weight loss effect of two more pounds lost per month compared to placebo for up to six months. There are no studies on the long-term effects of ephedrine or ephedra dietary supplements on weight loss, as the longest published study was six months.

Athletic Performance – The usage of dietary supplants containing ephedra for athletic performance has not been studied. There are a few studies on the using ephedrine for athletic performance. However, these studies used small samples of physically fit individuals, such as young male military recruits. Also, the studies only show it is only affects immediate performance for a very short term. One study found that caffeine needed to be used with ephedrine for it to affect athletic performance. There are no studies on the effect continued use of ephedrine has on athletic performance in the long-term.

Safety Issues – There is enough controlled trial evidence to show that supplements containing ephedrine or ephedra increased the occurrence of nausea, vomiting, anxiety, mood change, autonomic hyperactivity, and palpitations two to three times more than the placebo groups. The studies are not extensive enough to show the possibility of rare side effects/risks that occur in less than one person per thousand.

Most of the case reports are not documented well enough to be used to make an informed decision on the relationship between ephedrine or ephedra use and the adverse event that occurred. Ephedra usage was related to 2 deaths, 3 myocardial infarctions, 9 cerebrovascular accidents, 3 seizures, and 5 serious psychiatric cases as sentinel/unanticipated events. There were 43 cases determined as possible sentinel events with prior ephedr use and 7 cases of possible sentinel events with prior ephedrine use. Approximately half of the sentinel events were in people 30 or younger.

Conclusions: Ephedrine, ephedrine with caffeine, and dietary supplements containing ephedra with or without caffeine herbs are all related to moderate weight loss in the short term. There are no studies on long-term weight loss effects. Single dosages of ephedrine with caffeine have a moderate effect on immediate athletic performance. There are no trials with evidence that dietary supplements with ephedrine or ephedra improves athletic performance in the general population. Ephedra or ephedrine with caffeine usage is related to an increased risk of gastrointestinal, psychiatric, and autonomic symptoms.

There are adequate adverse event reports of death, myocardial infarction, cerebrovascular accident, seizure, and serious psychiatric illness in young adults that a hypothesis-testing study should be carried out. For example, a case-controlled study to prove or disprove the hypothesis that using ephedra or ephedrine might be casually related to these serious adverse events.