APA Dictionary of Psychology

n. a synthetic opioid that is an agonist at kappa opioid receptors and a partial agonist–antagonist at mu opioid receptors. It is used clinically for the management of moderate to severe pain, including migraine headaches, and as a preoperative medication. It is available in an injectable preparation and an intranasal spray, but the ease of use of the latter has made it a common drug of abuse. As with other opioid agents, butorphanol may cause respiratory depression, nausea, and dependence. U.S. trade name: Stadol.