Methadone Maintenance Therapy

Methadone maintenance therapy (MMT) is an opioid agonist treatment for opioid use disorder in which a patient receives a prescribed, supervised dose of methadone to prevent withdrawal and reduce cravings for illicit opioids such as heroin. Methadone binds the same brain receptors as other opioids but has a slower onset and longer action, so a single daily dose, with a minimum effective level near 60 mg, typically suppresses withdrawal for about 24 hours while blunting the euphoric effect of any illicit opioid used on top of it. Patients usually attend a clinic for daily observed dosing at first, moving to take-home doses as they demonstrate stability; the drug is dispensed as a liquid concentrate, dispersible tablet, or injectable. First introduced as a painkiller in the United States in 1947, methadone was adopted for maintenance treatment from 1964 onward and is now one of the most thoroughly studied addiction treatments, with research showing roughly half the mortality, less illicit drug use, better social functioning, and lower HIV transmission among patients retained in treatment, though it remains controversial as a therapy that substitutes one opioid dependence for a medically supervised one.