Methadone is a narcotic analgesic (pain killer). It is a synthetic opiate-like compound most commonly used to decrease the craving from heroin. It is used in detoxification from narcotic addiction or as a chemical maintenance therapy for those who can not remain narcotic free. It is cross tolerant to other narcotics and produces its own physical dependence if used long enough. Indeed, withdrawal from a methadone dependence is usually more difficult than from heroin because methadone is a longer acting drug. The withdrawal develops more slowly, it usually less intense, but is more prolonged. Withdrawal symptoms include muscle cramps, chills, sweating and nausea.
Effects from an oral dose are usually felt within 30 minutes and last 24 hours. Common side effects are drowsiness, lightheadedness, dryness of mouth, constipation and sweating. Tolerance develops to some of these symptoms, while other may be a result of excessive dosage.
Methadone, like all narcotics, depresses the central nervous system. Using methadone with other depressant drugs such as heroin, barbiturates or alcohol can greatly increase the depression of breathing, heart function and circulation. Alcohol also inhibits the way that methadone is broken down in the body.
Babies born to methadone-dependent mothers will also have a physical dependency.
Persons maintained on methadone can get a euphoric high from higher doses of heroin.