Efficacy and Safety of Ephedra and Ephedrine for Weight Loss and Athletic Performance - Efficacy and Safety of Ephedra and Ephedrine for Weight Loss and Athletic Performance
The goal of this study was to assess the safety and efficacy of ephedra and ephedrine for weight loss and athletic performance.
This was a meta-analysis of eligible studies and case reports involving ephedra and ephedrine used for weight loss and athletic performance with a defined follow-up. For adverse events ephedra or ephedrine had been used within the prior 24 hours, or an associated metabolite product was found in the blood or urine, and other potential causes had been excluded. The reviewers selected 52 controlled trials and 65 case reports after screening 530 articles for the adverse event analysis. Of 18,000 other case reports screened, 284 underwent a detailed review. Daily dose effects were tested defining ephedrine low dose as 10 to 20mg, medium 40 to 90mg, and high dose 100 to 150mg.
Pooled placebo controlled trials using ephedrine (n = 4), ephedrine + caffeine (n = 12), ephedra (n = 1), and ephedra + herbs with caffeine (n = 4) yielded estimates of weight loss of 0.6kg per month more than placebo. The confidence intervals were wide and none of the individual preparations was significantly better than placebo. At 4 months, ephedrine was associated with an average 11% weight loss. Weight loss with ephedrine + caffeine for 2 to 4 months was 1kg per month better than placebo (95%CI 0.7 to 1.3). A study comparing ephedrine + caffeine to dexfenfluramine showed no difference at 15 weeks. Safety data from 50 trials yielded a 2.2 to 3.6 fold increase in odds of psychiatric, autonomic, gastrointestinal complaints, and palpitations. From the cases reported to the FDA and manufacturers, there were 4 deaths, 5 MI’s, 11 CVA’s, 4 seizures, and 8 psychiatric cases, and about ½ of the events occurred in persons less than 30 years old. There was insufficient data to draw conclusions about event rates less than 1 per 1000. There was inadequate data to draw conclusions regarding the effect of ephedrine on athletic performance. However, ephedrine + caffeine demonstrated a 20-30% increase in athletic performance in 6 placebo controlled trials without an effect on oxygen consumption or time to exhaustion on exercise testing.
Among patients, ephedrine and ephedra promote modest short-term weight loss, but it is not clear whether the weight loss persists. Use of ephedra and ephedrine with caffeine is associated with cardiac, psychiatric, and gastrointestinal symptoms, and may be associated with cardiovascular deaths. Since no studies of the ephedrine alkaloids lasted the required 6 to 12 months and are not powered to determine safety, we don’t know the actual benefits or risk. Nor do we know the exposed population. How many students and athletes are taking these over-the-counter products? How many middle aged and elderly are using these products for weight loss without informing their doctors or a family member? Are we asking our patients with an MI or stroke whether they are taking these therapies? The public generally opposes FDA regulation for these and other herbal products, while millions of people are exposed to unknown risks.
Shekelle PG, Hardy ML, Morton SC, et al. Efficacy and Safety of Ephedra and Ephedrine for Weight Loss and Athletic Performance. JAMA. 2003;289:1537-1545.
Clinical Topics: Sports and Exercise Cardiology
Keywords: Dexfenfluramine, Seizures, Athletes, Students, Caffeine, Stroke, Oxygen Consumption, Weight Loss, Ephedra, Ephedrine, Athletic Performance
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