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Permitted non-hormonal performance-enhancing substances

Diana Robinson, MBBS FACSEP
Section Editor
Peter Fricker, MBBS, FACSP
Deputy Editor
Jonathan Grayzel, MD, FAAEM


Performance-enhancing drugs, supplements, and other substances have been used in a variety of settings by both athletes and non-athletes for decades. Individuals take performance-enhancing drugs and substances for a variety of reasons, which include improving athletic performance, increasing alertness, and improving appearance. Although the focus of the news media is on competitive athletes caught using banned hormonal agents (eg, androgens, growth hormones) [1], many non-hormonal drugs and other substances for performance enhancement are used, some of which are banned but others of which are permitted and freely available.

There has been a massive increase in the use of supplements in the sports community over the past couple of decades. Companies worldwide make a range of claims about the ergogenic benefit of many of these supplements. However, current evidence suggests that only a small number have demonstrable benefits for athletes. Importantly, throughout the world quality control for these substances is generally poor and regulations pertaining to their manufacture and marketing are weak, making it difficult for athletes to determine which supplements are safe, effective, and legal.

This topic will review some of the most common prescription medications and supplements that are not banned and are used by athletes for performance enhancement. Banned performance enhancing drugs, including hormonal agents, are discussed separately. (See "Prohibited non-hormonal performance-enhancing drugs in sport" and "Use of androgens and other hormones by athletes".)


Stimulants are considered both physical and cognitive performance enhancers. Beneficial effects for sport may include improvements in energy level, endurance, anaerobic performance, reaction time, concentration, and alertness. Relatively common potential adverse effects include headache, nausea, insomnia, anxiety, tremor, agitation, panic attacks, hypertension, and tachycardia. In extreme cases, stimulants may contribute to myocardial ischemia, stroke, psychosis, heatstroke, or rhabdomyolysis. While many stimulants (eg, methylhexanamine, amphetamine, oxilofrine) are banned by the World Anti-Doping Agency (WADA), a number are permitted and some are only monitored (eg, phenylephrine, synephrine, caffeine, bupropion). With the exception of caffeine, which is discussed below, all stimulants and their use for performance enhancement, including urine concentration thresholds for particular agents, are discussed separately. (See "Prohibited non-hormonal performance-enhancing drugs in sport", section on 'Stimulants: Overview of their effects'.)

Caffeine — Caffeine was included on the prohibited list from 1980 to 2003, and a urine concentration threshold was used to determine violations, but as of 2016, caffeine is only included on the WADA monitoring list. Athletes may ingest caffeine as part of their diet or as a supplement.

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Literature review current through: Nov 2017. | This topic last updated: May 09, 2017.
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