Narcotic analgesic

A substance that, when swallowed, inhaled, or injected, induces stupor, sleep, and insensibility. Narcotic analgesics induce a state of reversible depression on the central nervous system and are administered to relieve pain. However, the use of these drugs carries a high risk of psychological and physiological dependence, and side-effects include dose-related respiratory depression. The following narcotic analgesics are on the World Anti-Doping Agency's 2005 Prohibited List: buprenorphine, dextromoramide, diamorphine (morphine), fentanyl and its derivatives, hydromorphone, methadone, morphine, oxycodone, oxymorphone, pentazocine, and pethidine.