Description of Methadone
A synthetic opioid that is used as the hydrochloride. It is an opioid analgesic that is primarily a mu-opioid agonist. It has actions and uses similar to those of morphine. It also has a depressant action on the cough center and may be given to control intractable cough associated with terminal lung cancer.
Methadone is also used as part of the treatment of dependence on opioid drugs, although prolonged use of methadone itself may result in dependence.
Methadone is a synthetic opioid analgesic with multiple actions quantitatively similar to those at morphine. The most prominent of which involve the central nervous system and organs composed of smooth muscle. However, Methadone is more active and more toxic than morphine.
Methadone is indicated for relief of severe pain, for detoxification treatment of narcotic addiction, and for temporary maintenance treatment of narcotic addiction. The principal actions of therapeutic value are analgesia and sedation and detoxification or temporary maintenance in narcotic addiction.
The Methadone abstinence syndrome, although qualitatively similar to that of morphine, differs in that the onset is slower, the course is more prolonged, and the symptoms are less severe.
Mechanism of action
Methadone is a mu-agonist; a synthetic opioid analgesic with multiple actions qualitatively similar to those of morphine, the most prominent of which involves the central nervous system and organs composed of smooth muscle. The principal therapeutic uses for methadone are for analgesia and for detoxification or maintenance in opioid addiction.
The methadone abstinence syndrome, although qualitatively similar to that of morphine, differs in that the onset is slower, the course is more prolonged, and the symptoms are less severe. Some data also indicate that methadone acts as an antagonist at the N-methyl-D-aspartate (NMDA) receptor.
The contribution of NMDA receptor antagonism to methadone's efficacy is unknown. Other NMDA receptor antagonists have been shown to produce neurotoxic effects in animals.