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Richard Stockton
College Athletic Training
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| Examining Ephedrine- Containing Supplements By Ellen Coleman, RD, MA, MPH This article was published in the February 2003 Issue of the NATA News. |
| In many competitions, the difference between
winning and losing can occur in one play or the divisions of seconds.
So it is not surprising that athletes may utilize ephedrine-containing
supplements to improve their performance, have more energy or decrease
their body fat. Unfortunately, athletes who use ephedrine risk getting more than they bargained for from the drug. While it may help them run farther and faster, it can also make them prey to the myriad negative—even life-threatening—side effects. The fact is ephedrine use, at this stage of the game, is controversial at best, especially when you consider the NFL, NCAA and International Olympic Committee have all taken steps to keep it off the playing fields. Now, the FDA is getting into the discussion. what is ephedrine? What exactly is ephedrine? Classified as a sympathomimetic drug (a beta-1 and beta-2 adrenergic receptor agonist), it’s a central nervous system stimulant that increases serum levels of norepinephrine. The herbs ma huang, ephedra sinica and sida cordifolia contain ephedrine, which structurally is similar to amphetamines(1). Ephedrine is an effective bronchodilator due to its stimulation of beta–2 receptors in the lungs. However, it also stimulates beta-1 receptors in the heart and causes dose-dependent increases in heart rate and blood pressure. Drugs that are more selective beta-2 agonists are generally preferred for treatment of asthma(1). ephedrine’s role in athletic performance and weight loss Ephedrine’s appeal to users rests in the fact that it may do one or all of the following three things, depending on the individual: — Improve athletic performance by stimulating the central nervous system and by increasing heart rate and contraction force via activation of the beta-1 receptors. — Suppress appetite by increasing norepinephrine release through stimulation of adrenergic pathways in the hypothalamus(1). — Promote weight loss by increasing thermogenesis and resting energy expenditure via stimulation of the muscle beta-2 receptors to increase substrate metabolism. Users often combine the drug with caffeine and aspirin (called the “ECA stack”) to enhance its effectiveness as a weight loss agent. In this context, ephedrine stimulates the release of norepinephrine, which stimulates the release of adenosine and the synthesis of prostaglandins by the activated tissue. Adenosine and prostaglandins both inhibit the effect of norepinephrine. Caffeine opposes the effect of adenosine and so increases norepinephrine release. Aspirin inhibits the synthesis of prostaglandins and so enhances the effect of norepinephrine(1). side effects What users may not understand or take seriously when they seek the performance enhancing benefits of the supplement are the adverse effects it can produce. Ephedrine raises heat production and body temperature and increases the athlete’s risk of developing a heat injury during exercise in warm weather. In addition to increased heat production, other symptoms rang from dizziness, headache, gastrointestinal distress, irregular heartbeat and heart palpitations to heart attack, stroke, seizures, psychosis and even death. These side effects can vary among individuals and occasions and don’t always depend on how much is consumed. Also, combining caffeine (from coffee, Guarana, mate or Kola nut) with ephedrine-containing products (such as those mentioned earlier) greatly increases the risks(2,3). If the knowledge of these adverse effects isn’t enough to deter users, the International Olympic Committee, the NCAA and the NFL are hoping some of their policies banning the drug—and suspending players for doping—will be. At the very least, many in their ranks view the use of ephedrine-containing supplements to enhance performance as cheating. research findings Still, are these organizations’ concerns about ephedrine really valid? In December 2000, a prestigious medical journal set out to answer that question by examining the adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. The study, which was commissioned by the Food and Drug Administration, reviewed the records of 140 ephedra users who experienced complications (heart attack, stroke, seizure and death) between 1997 and 1999. These users were young and healthy—and some had only been taking ephedrine for a few days (2). results The researchers found that: — A combination of ephedrine and caffeine (0.8 to 1.0 mg of ephedrine per kg and 4 to 5 mg of caffeine per kg consumed 90 minutes before exercise) may improve both anaerobic and high-intensity aerobic performance (4,5). — Combining ephedrine and caffeine (20 mg ephedrine and 200 mg caffeine, consumed three times per day) with a low calorie diet (1,000 calories) may also help to promote weight loss in obese individuals(6,7). risks Yet the study highlighted the risks associated with ephedrine use. According to research: — One-third of the patients’ complications were definitely or probably caused by ephedrine use. Another third of the problems were possibly caused by ephedrine. — In one-fifth of the cases there was not enough information to determine the cause. The unreliable potency of ephedrine-containing supplements is also disturbing. A recent study analyzed the amount of ephedra alkaloids in 20 products and found they contained zero to more than 150 percent of the amount of ephedrine listed on the label. Half of the products tested varied more than 20 percent from their product label. There was also substantial lot to lot variation from the same manufacturers, indicating poor quality control (8). federal investigations Despite its effectiveness, in June 2002, Health and Human Services Secretary Tommy Thompson called for an extensive scientific review of ephedrine to address health concerns associated with its use. The Rand Corporation is conducting this comprehensive review of the existing science on ephedrine, and the National Institutes of Health will use this information to evaluate the safety of the product(9). Just two months later in August, the FDA asked the U.S. Department of Justice to pursue a criminal investigation of Metabolife, a leading producer of ephedrine-containing supplements. The agency wanted to know if Metabolife made false statements to the FDA regarding the existence of adverse event reports. Metabolife stated that 400,000 people called between 1997 and 2001 and reported 13,000 incidents of health-related issues(9). The FDA has tried to obtain these adverse event reports since 1997, even resorting to litigation, but has been unsuccessful. “Metabolife has refused and resisted us every step of the way,” said FDA Deputy Commissioner Lester Crawford, adding that the FDA is so concerned about the volume of reports that it has set up a special task force to review the records(9). “Given their long history of being uncooperative, we view their offer to make these reports available now to be disingenuous.” In October 2002, Thompson urged the FDA to recommend strong mandatory warning labels for ephedrine-containing products. The FDA is working on proposed regulations regarding Good Manufacturing Practices for dietary supplements. These measures do not preclude further actions as a result of the Rand Corporation’s review of ephedrine. In addition, the FDA announced a new program to analyze all herbal ephedrine products to ensure they contain natural (not synthetic) ingredients as required by law. It is illegal for companies to market non-herbal synthetic ephedrine products as dietary supplements(10 ). conclusion Although ephedrine may improve athletic performance, the risks associated with this supplement far outweigh the benefits. Supplements containing ephedrine will not enable athletes to safely reach their goals. Sound nutrition, hydration and training programs will. products containing ephedrine
references 1. Rawson ES, Clarkson PA. Ephedrine as an ergogenic aid. Performance-enhancing Substances in Sport and Exercise. Ed Bahrke MS, Yesalis CE. Human Kinetics. 2002. 2. Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. NEJM. 343:1833-8, 2000. 3. Public Citizen Health Research Group. Petition to the Food and Drug Administra-tion (FDA) requesting the ban of production and sale of dietary supplements containing ephedrine alkaloids. (HRG Publication #1590). http: //www.citizen.org/publications/release.cfm?ID=7053 4. Bell DG, McLellan TM, Sabiston CM. Effect of ingesting caffeine and ephedrine on 10-km run performance. Med Sci Sports Exerc. 34:344-9, 2002. 5. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc. 33:1399-403, 2001. 6. Astrup A, Breum L, Toubro S, Hein P, Quaade F. The effect and safety of an ephedrine/caffeine compound compared to ephedrine,caffeine and placebo in obese subjects on an energy restricted diet. A double blind trial. Int J Obes Relat Metab Disord. 16(4):269-77, 1992. 7. Astrup A, Buemann B, Christensen NJ, Toubro S, Thorbek G, Victor OJ, Quaade F. The effect of ephedrine/caffeine mixture on energy expenditure and body composition in obese women. Metabolism. 41:686-8, 1992. 8. Gurley BJ, Gardner SF, Hubbard MA. Content versus label claims in ephedra-containing dietary supplements. Am J Health Syst Pharm. 57:963-9, 2000. 9. Food and Drug Administration. FDA News: Statement from FDA Deputy Commissioner Crawford regarding Meta-bolife. August 15, 2002. http: //www.fda.gov/bbs/topics/NEWS/2002/NEW00828.html 10. Food and Drug Administration. FDA News: Secretary Thompson urges strong warning labels for ephedra. October 8, 2002. http://www.fda.gov/bbs/topics/ NEWS/2002/NEW00844.html. Ellen Coleman works with athletes at The Sports Clinic in Riverside, Calif., and is a nutrition consultant for the Los Angeles Lakers and Anaheim Angels. |
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