What is the difference between depressant and antidepressant?

[Tan Elaine]

What is the difference between "depressant' and anti-'depressant'?

It seems they are the same. Thanks.

 

[Charlie Bernstein]

Depressants are drugs that make people sleepy. Sleeping pills and alcohol are depressants.

Anti-depressents are drugs that make people happier. Prozac is an anti-depressant.

Stimulants are drugs that make people alert. Amphetamines and caffeine are stimulants. They have the opposite effect of depressants.

 

[GoesStation]

The prefix anti means "against". For example, in BrE people describe circular motion as clockwise or anti-clockwise. (We say counter-clockwise in AmE.)

 

[emsr2d2]

If you had looked up the definition of "anti", how did you come to the conclusion that "depressant" and "anti-depressant" meant the same?