5. Heroin

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We don’t have any specific information on whether this was a treatment that actually worked, but it may have made the patient less aware of their ailment after a dose or two. Heroin was once manufactured by Bayer and sold to the public as a treatment for cough. It’s probably not necessary to remind people that heroin really isn’t much of a cure for anything, unless you believe that not being a drug addict is some form of illness!