Comparative Multiple-dose Study of Ketorolac Tromethamine and Diflunisal for Pain Following Orthopaedic Surgery

A total of 100 patients were enrolled after orthopaedic surgery in a multiple-dose, randomized, double-blind, parallel-group study to compare the analgesic efficacy and safety of 10 mg ketorolac trom-ethamine given orally four times daily for 3 days with 500 mg diflunisal given orally twice daily plus placebo twice daily for 3 days. Ketorolac was significantly (P = 0.04) superior to diflunisal in reducing the pain severity during the first 9 h of treatment; a difference possibly related to the more flexible dosage regimen of ketorolac. Patients and the in-vestigator, however, rated ketorolac and diflunisal as being equally effective in terms of the overall drop in severity of pain and pain relief at the end of days 1,2 and 3. Ketorolac-treated patients reported a total of nine adverse events and diflunisal-treated patients reported 13. It is concluded that in the treatment of acute post-operative pain a drug with a more flexible dosage regimen may provide superior pain relief. KEY WORDS: Ketorolac tromethamine; diflunisal; orthopaedic surgery; post-operative pain