Background Ultramarathon races have gained popularity in recent years and test the limits of human endurance. Runners often take analgesic medication during endurance foot races which may lead to gastrointestinal complications, altered renal function, and is associated with the development of hyponatremia and rhabdomyolysis.

Methods We conducted a prospective survey study to gather data on prevalence, awareness, and reasons for consumption of analgesic medication used among ultramarathon runners during the Al Andalus Ultimate Trail 2012. Data were obtained post race using a direct-interview technique on standardized questionnaires.

Results Thirty-two ultramarathon runners (26 male, 6 female, mean age 39.5±7.9, previous ultramarathon experience 7.7±9) participated in the study. The majority of runners (53%) did not take any form of analgesic; 44% said they had used them sometime during the race and training; and 3% had used them regularly. Nonsteroidal anti-inflammatory drugs (NSAID) were most commonly used (60%) followed by Paracetamol (40%). The reasons for use were to reduce musculoskeletal pain (65%) or to combat fatigue (24%). All runners felt that taking an analgesic provided effective relief. Only 6 % of athletes obtained them through a prescription from their doctor. The main sources of recommendation were fellow runners and friends (56%), self initiative (22%) or coaches (6%). They were mainly obtained in shops (47%) and chemists (47%) and rarely on the Internet (6%). Two thirds of runners said they were aware of adverse effects, naming mainly renal failure (27%), gastrointestinal problems (18%) and liver failure (9%).

Conclusion We found a high prevalence of analgesic medication use among ultramarathon runners. A third of runners were not aware of any adverse effects or dangers associated with analgesic consumption. Analgesic medication may have deleterious effects on the body and its performance. Pre-race education programmes may help increase awareness of effects, risks and appropriate use, and consumption.