Methadone is a synthetic opioid analgesic agonist with strong oral effectiveness and long-lasting properties commonly used for the detoxification and maintenance of individuals with opioid/heroin-dependency. Less commonly, methadone is also used as an analgesic in the treatment of chronic pain. Methadone exerts its major pharmacological effects on the central nervous system by substantially reducing the severity of withdrawal symptoms for opioid and heroin addicts thus minimizing the likelihood of drug craving over an extended period of time. Methadone maintenance programs (MMPs) typically dispense the oral form of methadone in single dose not exceeding 80-100 milligrams daily lasting 24-36 hours. Less frequent administration aids in reducing harmful effects. Although maintenance patients have been known to receive up to 180 mg of the drug daily, doses of 50 mg or less have proven fatal in non tolerant patients.
Methadone can be detected in plasma within 30 minutes following oral ingestion, reaching a peak concentration at ~4 hours. Adverse pharmacological effects of methadone include sedation, dizziness, weakness, nausea, loss of appetite, headache, insomnia, constipation, decreased sex drive, bradycardia, palpitations, and respiratory depression.
Methadone medical expert witness specialties include addiction psychiatry and toxicology.