Stimulants (also referred to as
psychostimulants) are
psychoactive drugs that induce temporary improvements in either mental or physical functions or both. Examples of these kinds of effects may include enhanced
alertness,
wakefulness, and locomotion, among others. Due to their rendering a characteristic "up" feeling, stimulants are also occasionally referred to as "
uppers".
Depressants or "downers", which decrease mental and/or physical function, are in stark contrast to stimulants and are considered to be the functionally opposite
drug class. Stimulants are widely used throughout the world as
prescription medicines and without prescription both as
legal substances and
illicit substances of
recreational use or
abuse.
