Methadone is a synthetic opioid. It is most commonly used as a form of maintenance therapy or to help in detox, in people with dependence to opioids.
Methadone was developed in Germany in 1937 by Gustav Ehrhart and Max Bockmühl, that could be created with readily available precursors.
On September 11, 1941 Bockmühl and Ehrhart filed an application for a patent for a synthetic substance they called Polamidon, and whose structure had only a slight relation to morphine or other opiate alkaloids. It was brought to market in 1944 and was widely used by the German army during WWII.
Methadone was introduced into the United States in 1947 by Eli Lilly and Company, as an analgesic under the trade name Dolophine.
NOTE: Do not stack this with more Methadone, as this substance takes fairly long to peak.