Methadone is a synthetic opioid with analgesic activity. Methadone mimics the actions of endogenous peptides at CNS opioid receptors, primarily on the mu-receptor and has actions similar to those of?morphine?and?morphine-like agents. The characteristic?morphine-like effects include analgesia, euphoria, sedation, respiratory depression, miosis, bradycardia and physical dependence. However, the detoxification symptoms between?morphine-like agents and methadone differ in that the onset of methadone’s withdrawal symptoms is slower, the course is more prolonged and the symptoms are less severe.