Methadone is a powerful opioid drug, with similar effects to heroin, morphine or codeine. It is commonly prescribed to people with an addiction to heroin or other opioids, as a step towards coming off drugs.
Methadone stays in the body for longer than other opioids, so a single dose helps addicts to get through the day without cravings or withdrawal symptoms. It is usually taken by mouth as a liquid, eliminating the risks that come with injecting drugs.
It works by mimicking endorphins, the body’s natural pain-killing chemicals, but its slow action means it causes less of a high than heroin. Like other opioids, it slows respiration, and taking too much can kill by stopping breathing altogether.
The idea of methadone maintenance therapy is that addicts are stabilised and don’t have to worry about getting their next fix. That might help them to address any problems they have, and when they are ready, they can be weaned off the drug by reducing their dose gradually. But coming off methadone can be even harder than coming off heroin.
Although it has been used in many countries for decades, methadone maintenance therapy remains controversial. Studies show that it keeps patients in therapy and decreases heroin use better than treatments that do not use opioid replacements. However, it does not have a statistically significant effect on criminal activity or death. Critics say the treatment merely substitutes one addiction for another. Some countries favour prescribing heroin to addicts, and some trials have suggested this results in better health and less crime. Sam Wong
Methadone maintenance treatment can keep people who are dependent on heroin in treatment programs and reduce their use of heroin. Methadone is the most widely used replacement for heroin in medically-supported maintenance or detoxification programs. Several non-drug detoxification and rehabilitation methods are also used to try and help people withdraw from heroin. However the review found that people have withdrawn from trials when they are assigned to a drug-free program. Consequently, there are no trials comparing methadone maintenance treatment with drug-free methods other than methadone placebo trials, or comparing methadone maintenance with methadone for detoxification only. These trials show that methadone can reduce the use of heroin in dependent people, and keep them in treatment programs.