The World Anti-doping Agency Prohibited list identifies substances and methods prohibited in- and out-of-competition, in-competition only, and in particular sports. The substances and methods on the List are classified by different categories (such as steroids, stimulants, or gene doping).
An athlete may be permitted to use a prohibited substance or method for medical reasons, if they obtain a Therapeutic Use Exemption (TUE).
The Prohibited List is updated annually following an extensive consultation process facilitated by WADA. Additional substances or methods may be added to the List at any time during the year but this will only occur after a three month notice period.