From Legal to Illegal and Back: The Evolving Status of Three Notable Drugs

The three drugs-mostly cannabis, cocaine, and heroin-have seen significant historical legal permutations. What used to be considered medicinally valuable initially but has gradually, due to societal concerns, turned out to be less favored for their use became prohibited. Cannabis was once extensively used until the early 20th century; cocaine was added to tonics and soft drinks and then got criminalized in the early 1900s. Heroin used initially for coughs similarly fell out of favor. Recently, though, all three have enjoyed a revival of legal status for medical use, reflecting changing attitudes toward drug policy and public health. 

Source: The Conversation