Heroin was originally sold as cough medicine.
Heroin developed by Bayer was used to suppress cough in the 19th century and was marketed as a non-addictive substitute to morphine which was very addictive. It was originally introduced as cough medicine in children and was sold as tonics, lozenges, and drops. However, Heroin turned out to be a very addictive drug that had severe side effects. Soon people started becoming tolerant and several addiction cases were reported. The drug was banned in the USA IN 1924.