Comparison of diflunisal and piroxicam in the management of patients with osteoarthritis.

An open-label comparison of diflunisal, a nonacetylated salicylate nonsteroidal anti-inflammatory drug (NSAID), and piroxicam, an NSAID belonging to the oxicam family, was conducted in patients with osteoarthritis. Efficacy assessments were made biweekly by the physician and patients during a 12-week treatment and observation period. The physician's evaluations showed that both drugs resulted in significant reductions in knee pain, tenderness, swelling, stiffness, and difficulty walking. A greater number of statistically significant differences were noted with diflunisal than with piroxicam, but there were no statistically significant differences between the two treatment groups. Patients' efficacy ratings tended to favor diflunisal, and diflunisal was significantly more effective than piroxicam in relieving night pain. Seventy-five percent of patients receiving diflunisal and 40% of those receiving piroxicam considered their condition improved after treatment; however, the proportion of good to excellent drug ratings was similar for the two drugs. Both drugs were generally well tolerated. Adverse effects were encountered in five (28%) of 18 patients given diflunisal and in four (33%) of 12 patients given piroxicam. Six patients were withdrawn from the study because of side effects, four from the piroxicam group and two from the diflunisal group. In this study, diflunisal was found to be an effective and well tolerated drug for use in the management of osteoarthritis.