Heroin
Bayer Heroin bottle
Heroin (diacetylmorphine), now illegal as an addictive drug, was trademarked and marketed by Bayer as a cough suppressant and non-addictive substitute for morphine from 1898 to 1910.[16] Bayer scientists were not the first to make heroin, but their scientists discovered ways to make it, and Bayer led commercialization of heroin.[17] Heroin was a Bayer trademark until after World War I.[18]
Phenobarbital
In 1903, Bayer licensed the patent for the hypnotic drug diethylbarbituic acid from its inventors Emil Fischer and Joseph von Mering. It was marketed under the trade name Veronal as a sleep aid beginning in 1904. Systematic investigations of the effect of structural changes on potency and duration of action at Bayer led to the discovery of phenobarbital in 1911 and the discovery of its potent anti-epileptic activity in 1912. Phenobarbital was among the most widely used drugs for the treatment of epilepsy through the 1970s, and as of 2014, remains on the World Health Organization's list of essential medications.[19][20]