Comparison of diflunisal and dextropropoxyphene napsylate in the treatment of post-operative pain.

A double-blind study of 43 patients undergoing excision of haemorrhoids under spinal anaesthesia was carried out to compare the analgesic effects of diflunisal (DFL, 21 patients) and dextropropoxyphene napsylate (DPN, 22 patients) on post-operative pain. Eleven patients (25%) reported no significant pain during the study indicating that they had needed no analgesic medication (4 in the DFL group and 7 in the DPN group). Thus 17 patients in the DFL group and 15 patients in the DPN group contributed to the analysis data. Seven patients in the DFL group and 9 patients in the DPN group needed additional analgesic therapy on the day of surgery. After the day of surgery the analgesic effect of both of the test medications was sufficient but DFL proved to provide slightly better pain relief than DPN. Two patients in each study group had mild adverse reactions including vomiting and epigastric pain, which were probably drug related. It is concluded that both DFL and DPN are safe and sufficiently effective treatments for pain after haemorrhoidectomy but not until one day after surgery.