Ephedrine and supplements derived from Ephedra plants can cause autonomic hyperactivity (e.g., heart palpitations, tremors, twitching, insomnia, and sweating), gastrointestinal problems (e.g., nausea, vomiting, reflux, and heartburn), and psychiatric symptoms (e.g., agitation, lowered mood, irritability, and anxiety).[1][2] Ephedra supplements have also been implicated in adverse cardiovascular and cerebrovascular outcomes including stroke, heart attack, and death.[3][2]
Furthermore, ephedrine and its derivatives (pseudoephedrine, methylephedrine, etc.) are currently included on the prohibited list of substances issued by the World Anti-Doping Agency (WADA). Therefore, athletes who use ephedra supplements or over-the-counter drugs containing ephedrine (e.g., decongestants) must ensure that they are following the rules of their sport and holding the necessary therapeutic use exemptions (TUE).