Opioids.

The major clinical uses for opioids are to control pain, suppress cough, and to treat diarrhea. These drugs, however, have the potential for abuse. It is postulated that the significant mood-altering effects of opioids combined with their pharmacology, in which tolerance and physical and psychological dependence occur, account for their abuse liability. A classification of the groups of patients that commonly present with complications of opioid use is reviewed briefly before discussing the clinical pharmacology of the opioids and their acute and toxic effects.