Methadone is a synthetic opioid most often used to treat opioid dependence. The Schedule II drug was originally developed by the Nazis during World War II in response to a threat of an opium shortage. It was introduced into the United States in the 1940s as an analgesic that would bring pain relief similar to that of morphine. While it is still sometimes used as an analgesic, methadone became popular with physicians as a way to treat opiate addictions, particularly heroin. An estimated one million Americans are addicted to heroin, and about 120,000 people take methadone as part of their recovery treatment. Studies have shown that methadone is useful in the treatment of opioid addiction because it blocks the effect of other opiates in the brain and reduces withdrawal symptoms associated with opiate abuse. When used as prescribed, methadone does not produce a “high,” acting instead as a mild sedative. Like most prescription painkillers, it can be very dangerous when taken illegally or not taken as prescribed. Methadone has addictive properties, and the drug’s critics say it does not help treat the underlying root of an addiction. Methadone proponents encourage its usage for the drug’s overall efficacy for opiate addicts, its long-lasting effect, and affordability. Methadone therapy was originally developed as a short-term treatment option for heroin. The current medical consensus is that treatment should continue as needed and as prescribed by an individual’s doctor. Methadone treatment is also more successful if used in conjunction with cognitive behavioral therapy and/or a 12-step program.