WADA moves to ban carbon monoxide rebreathers as a performance-enhancing method

A year after controversy erupted over the use of carbon monoxide rebreathers by some of professional cycling’s top teams, the World Anti-Doping Agency (WADA) has added the use of the gas as a performance-enhancing method as a banned method starting in 2026.

“The non-diagnostic use of carbon monoxide (CO) was added to the Prohibited Methods as a new section, M 1.4,” WADA stated in its summary of the major modifications to the Prohibited List. “It can increase erythropoiesis under certain conditions.”