Narcotic

A narcotic is a drug that causes a loss of feeling, or paralysis. The name "narcotic" was probably first used by the Greek physician Galen. Galen listed mandrake root or poppy juice among the main examples for such substances.
Today, the word "narcotic" is mainly used for illegal drugs, which do not necessarily have these properties. Marijuana and cocaine are considered to be narcotics, even they do not have the medical properties described.