define depressant drug
A depressant, or central depressant, is a drug that lowers neurotransmission levels, which is to depress or reduce arousal or stimulation, in various areas of the brain.Depressants are also occasionally referred to as downers as they lower the level of arousal when taken.timulants or uppers increase mental and/or physical function and are the functional opposites of depressants. Depressants are widely used throughout the world as prescription medicines and as illicit substances.