Methadone is a narcotic, controlled substance most famous for being the treatment of choice in the treatment of heroin addiction. Methadone is a synthetic derivative of morphine, according to the University of Maryland Center for Substance Abuse Research. Methadone is also used for pain relief, especially in patients suffering from severe protracted pain, such as in cancer patients. Methadone is mainly available for oral use. Methadone is considered generally a safe drug; yet its prolonged use may be associated with long-term side effects.
Drug Dependence
While methadone is used to help wean patients off opioids and heroin, some patients become dependent on methadone, as noted by University of Maryland Center for Substance Abuse Research. Methadone functions through occupying the opioid receptors in the brain, also known as the dopamine receptors, for a prolonged period of time, causing the patient to have fewer highs and lows than other shorter-acting opioid drugs. Methadone, as opposed to morphine, is long-acting and of slower onset action. This makes it less likely to produce s a state of euphoria, or the addictive "high". However, some patients remain depend on methadone for years for control of withdrawal symptoms; such patients are said to be placed on methadone maintenance treatment, as described by the Office of National Drug Control Policy.
Respiratory Problems
The Merck Manuals Online Medical Library mentions the potential of respiratory depression by the prolonged use of methadone. These respiratory concerns are more likely to surface if the patient has an underlying lung disease, such as emphysema, obstructive pulmonary conditions or skeletal deformities, has reduced the lungs' aeration capacity. Respiratory depression can occur even with use of therapeutic doses.
Heart Problems and Drowsiness
The Merck Manuals Online Medical Library states that there are possible side effects, although rare, for the use of methadone, such as sedation and drowsiness. It can also potentially cause some cardiac anomalies related to the effect it has on the electrical conduction of the heart that regulates the heart rate. The National Highway Traffic Safety Administration warns methadone users that their visual acuity and reaction time may be impaired. It also cites several studies that confirm that methadone may impair the driving ability of otherwise healthy people.
