Dezocine

Dezocine (Dalgan, WY-16225) is an opioid analgesic related to pentazocine, with a similar profile of effects that include analgesic action and euphoria at low doses, but produces dysphoria and hallucinations at high doses, most likely due to action at κ-opioid receptors.

Dezocine has been found to be an effective painkiller comparable to meperidine (pethidine), and so is a more effective analgesic than pentazocine, but causes relatively more respiratory depression than pentazocine. It is a useful drug for the treatment of pain, but side effects such as dizziness limit its clinical application, and it can produce opioid withdrawal syndrome in patients already dependent on other opioids.

Dezocine is unusual among opioids as it is the only primary amine known to be an active opioid. It is a mixed agonist-antagonist as with other drugs in this class, and despite having a stronger respiratory depressant effect than morphine, dezocine shows a ceiling effect on its respiratory depressive action so above a certain dose this effect does not get any more severe.