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Methadone is a synthetic opioid analgesic synthesized in 1937 by German scientists Max Bockmühl and Gustav Ehrhart at IG Farben (Hoechst-Am-Main) who were searching for an analgesic that would be easier to use during surgery and also have low addiction potential. Methadone is a Schedule I drug under the Single Convention on Narcotic Drugs[1].
On September 11, 1941 Bockmühl and Ehrhart filed an application for a patent for a synthetic substance they called Hoechst 10820 or polamidon and whose structure had no relation to morphone or the opioid alkaloids (Bockmühl and Ehrhart, 1949). Although chemically unlike morphine or heroin, methadone also acts on the opioid receptors and thus produces many of the same effects. Chemically, methadone is the simplest of the opioids.
Methadone was introduced into the United States in 1947 by Eli Lilly and Company as an analgesic (They gave it the trade name Dolophine® which is now registered to Roxane Laboratories). Since then, it has been best known for its use in treating narcotic addiction, though it is also used in managing chronic pain due to its long duration of action and very low cost. In late 2004, the cost of a one month supply of methadone is 20 USD, as compared to an equivalent analgesic amount of Demerol at 120 USD. The old name Dolophine comes from the German Dolphium. The name derives from the Latin "dolor" (pain).
Methadone (as Dolophine) was first manufactured in the USA by Mallinckrodt, a St. Louis-based subsidiary of the Tyco International corporation. Mallinckrodt held the patent up until the early 1990s. Today a number of pharmaceutical companies produce and distribute methadone. However, the major producer remains Mallinckrodt. Mallinckrodt sells bulk methadone to most of the producers of generic preparations and also distributes its own brand name product in the form of tablets, dispersable tablets and oral concentrate under the name "Methadose" in the United States. Generally, one will only hear "dolophine" used by older addicts who used the product in the 1960's and 1970's. Medical professionals who believe that dolophine is the generic name for methadone, when actually it is the reverse, may also use the old brand name. Myths abound about methadone and this is just another one.
Because of its slow metabolism and very high lipid solubility, methadone is longer lasting than morphine-based drugs. Methadone has a typical half life of 24 hours or more, permitting administration only once a day in heroin detoxification and maintenance programs. Methadone is almost as effective when administered orally as by injection. Tolerance and dependence may develop, and withdrawal symptoms, though they develop more slowly and are less acutely severe than those of morphine and heroin, are more prolonged. Some heroin addicts feel that it is actually harder to quit methadone than heroin itself. Methadone is encountered on the illicit market and has been associated with a number of overdose deaths, though the illicit demand comes primarily from opioid addicts unable to get into a legal methadone program; addicts seeking a high strongly prefer shorter-acting opioids. Canadian authorities--in an attempt to deter addicts from misuse of oral dosages of Methadone--at one time packaged the drug in combination with Tang™. Surely, they thought, nobody would be so foolish as to intraveneously inject such a combination. This was not the case.
Closely related to methadone, the synthetic compound levo-alphacetylmethadol or LAAM (ORLAAM) has an even longer duration of action (from 48 to 72 hours), permitting a reduction in frequency of use. In 1994 it was approved as a treatment of narcotic addiction. Like methadone, LAAM is in Schedule II of the United States Controlled Substances Act.
Buprenorphine has also been used in the treatment of narcotic addiction. In October, 2002, the FDA approved two compounds containing buprenorphine (Subutex and Suboxone) for the treatment of narcotic addiction. It is interesting to note that Subutex and Suboxone are in Schedule III of the United States Controlled Substances Act, which allow for their use on an outpatient basis, unlike methadone and LAAM. In the UK however both buprenorphine and methadone are regularly used for outpatient treatment of opiate addiction, but LAAM was withdrawn from the market in April 2001 due to a risk of life-threatening cardiac arrhythmias.
Another close relative of methadone is dextropropoxyphene, first marketed in 1957 under the trade name of Darvon®. Oral analgesic potency is one-half to one-third that of codeine, with 65 mg approximately equivalent to about 600 mg of aspirin. Dextropropoxyphene is prescribed for relief of mild to moderate pain. Bulk dextropropoxyphene is in Schedule II of the United States Controlled Substances Act, while preparations containing it are in Schedule IV. More than 100 tons of dextropropoxyphene are produced in the United States annually, and more than 25 million prescriptions are written for the products. This narcotic is associated with a number of toxic side effects and is among the top 10 drugs reported by medical examiners in recreational drug use deaths.
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