The Global Drug Reference Online is a website that Olympic athletes and their support teams from the United States, Canada and the United Kingdom can check to see if any drug they take is prohibited by the World Anti-Doping Agency (WADA). The purpose, of course, is to make sure the athletes aren't taking any drug that would give an unfair advantage to the athlete. The site allows athletes to make sure any medication they are taking, even for routine health problems, i.e. allergies, doesn't contain any ingredients that are prohibited by WADA. Visitors can do a mock search to see that the "user type", "sport" and "nation of purchase" are all factors in whether the drug is prohibited or not. The "user type" includes "athlete", "coach", "medical professional", "sports administrator", and "parent". Many of the mistakes the athletes could make in regard to determining if the drug is prohibited are mentioned in the "FAQs" section, and the burden of proof is clearly on them.