A PHARMACOLOGICAL COMPARISON OF PHENAZOCINE HYDROBROMIDE AND MORPHINE SULFATE AS NARCOTIC ANALGESICS

¹ Pharmacology Section, Smith Kline & French Laboratories, Philadelphia, Pennsylvania

The pharmacological actions of phenazocine, a new potent narcotic analgesic, have been shown to be qualitatively similar to those of morphine. Phenazocine, like morphine, produces analgesia, tolerance, respiratory depression, hypotension, bradycardia, colon spasm, excitation and mydriasis in cats, possesses antiemetic properties and its effects are antagonized by N-allylnormorphine. The results indicate, however, that phenazocine exhibits a greater separation than morphine between its analgesic activity on the one hand, and its cardiovascular-respiratory depressant effects in anesthetized dogs on the other. The separation of analgesic activity of phenazocine from undesirable effects was also demonstrated by phenazocine's lack of emetic effect in dogs. The results of this study indicate that phenazocine is a promising agent for the treatment of pain.