Druglink article 1996 – A secret history? The truth behind methadone by Andrew Preston and Gerald Bennett

In 1938, two German scientists discovered what is now known as methadone. They passed it on to the military authorities but little was done about the drug and it lay unexploited until the end of the war, when commercial production began in America. It would be nearly twenty years, however, before the value of methadone as a substitute for heroin was recognised.

A secret history? The truth behind methadone (PDF)