Clinical pharmacology of opioid analgesics.

Opioid analgesics continue to be the most important drugs in modifying the response to pain. Their versatility is attested by their frequent use in both postoperative and intraoperative management of pain. Recent findings regarding the mechanism of action of opioids may signal the introduction of newer, more effective, and less addictive agents. So far, this has not occurred. However, opioids with mixed agonist-antagonist properties have offered some utility. The adverse effects of nausea and dysphoria and the more serious effects of respiratory depression continue to be a problem, as does the possibility of abuse. Nonetheless, the clinical experience with opioids in control of pain is uncontested. Until better drugs are developed, opioids will form the basis for the control of acute pain by the dental practitioner.