What are the drugs that are often abused but used as medicines to help patients cope with mental illnesses like depression and insomnia?

Step-by-step solution

Heroin is a depressant that slows down body functions.Heroin is usually taken by snorting and injectionNatural cannabinoids are obtained from the inflorescences of the plant Cannabis sativa. Cannabinoids are known for their effects on the cardiovascular system of the body.Coca Alkaloid or cocaine interferes with the transport of the neuro-transmitter dopamine. Drugs like barbiturates, amphetamines, benzodiazepines, etc. that are normally used as medicines to help patients cope with mental illnesses like depression