For what purpose haldol is used?

Haldol is a "Heavy Tranquilizer", usually given to people suffering Schizophrenia or a psychotic episode. It is intended to slow down imagination/creativity areas of the brain, but impairs the entire brain in doing so.

Compared to "Mild Sedatives" such as valium, xanax, etc. Haldol is about 10-50 times more powerful, but doesn't slow down the body as much as the brain, leading to shakes and poor muscle/motor control aka "Haldol Shuffle". Good answer!. I'd like to add that Haldol (or haloperidol) is also used to treat Tourette's Syndrome. And Xanax (alprazolam) is more of an anti-anxietal than a tranquilizer (I'll leave you to guess how someone somewhere actually made that distinction).