Ephedrine

Ephedrine is classified as a sympathomimetic drug and central nervous system stimulant. The action of ephedrine is similar to that of amphetamines, to which it is structurally related. Its ability to act as a sympathetic agonist and increase themogenesis has led to its use in weight loss. As a central nervous system stimulant, it is used to reduce fatigue and increase alertness.

There are few data on the extent of ephedrine use in athletes. Gruber and pope (1998) noted that of 64 women weight lifters interviewed, 36 (56%) reported taking some form of ephedrine. The prevalence of ephedrine use in professional sport, where there may be no drug testing at all, is almost completely unknown.

Throughout the past 30 years, athletes in a variety of sports have tested positive for ephedrine or pseudoephedrine. Some claimed that they were simply taking over-the-counter cold medicine or that they were ingesting a supplement that they were unaware contained ephedrine. The consequences of these positive drug tests have ranged from rather mild to quite severe.

The ephedrine content of ephedra plants can vary widely and is dependent on where the plant is grown, the type of four studies indicate that pseudo-ephedrine supplementation in healthy young subjects does not enhance exercise performance during cycling or treadmill running at sub-maximal or maximal exercise intensities and has only small effects on selected physiological parameters. Further, there is no indication that pseudo-ephedrine supplementation reduces perceived exertion during exercise.

Although limited information on the performance-enhancing effects of ephedrine and pseudo-ephedrine is available at this time, some conclusion can be drawn. Ephedrine supplementation has been shown to have ergogenic effects only when it is ingested with other drugs such as theophyline or caffeine. In fact, there are currently no data to support an ergogenic effect for ephedrine ingestion prior to exercise. It is clear that pseudo-ephedrine ingestion does not improve exercise performance on sub-maximal or maximal exercise and does not reduce ratings of perceived exertion during exercise. Furthermore, the increase in heart rate, blood pressue, tremor, and anxiety caused by ephedrine use may actually result in an impairment in athletic performance, especially in doses larger that those used in the research studies.