Objective Pseudoephedrine is a stimulant that can be purchased over-the-counter to relieve symptoms of nasal and sinus congestion. Owing to its similar composition to ephedrine and other amphetamines, pseudoephedrine mirrors some of its ergogenic effects. This study investigates its possible ergogenic effect through a systematic review. Our primary aim was to determine the effects of pseudoephedrine in sport and its potential for performance enhancement.

Design We searched EMBASE, MEDLINE, PsychINFO and The Cochrane Library for trials conducted from their beginning to March 2015. Any published trial that used randomised assignment to the intervention and control groups in full text and measured pseudoephedrine as an independent variable were included.

Results Overall, the review showed that the ergogenic effect of pseudoephedrine is dose-dependent. None of the reviewed studies showed an ergogenic effect at the therapeutic dose of the drug (60–120 mg); however, supratherapeutic doses (≥180 mg) yielded clinically significant results.

Conclusions Owing to the limitations of the published studies in this field, we were unable to make any firm conclusions with respect to the overall effect of pseudoephedrine and its ergogenic effect. It is evident that there is a correlation between the dose administered and its ergogenic effects, but it is also evident that the side effects of using above the therapeutic dose outweigh the possible benefits of using pseudoephedrine in sport. Further research with larger sample sizes is required to determine the relationship between doses (≥180 mg) and concentrations in urine that cause an ergogenic effect.