Diflunisal and ibuprofen: effects on gastric and duodenal mucosa in patients with osteoarthritis.

Patients with osteoarthritis make up the largest group of users of nonsteroidal anti-inflammatory drugs (NSAIDs), but the effects of these agents on the gastrointestinal mucosa of such patients have not been well studied. This article describes a short-term comparison of two widely used NSAIDs, diflunisal and ibuprofen, in patients requiring these medications for their osteoarthritis. Efficacy, tolerability, and endoscopically documented effects of these drugs on the gastric and duodenal mucosa were assessed. Consenting, eligible patients were randomly assigned to one of the two study drugs for a two-week course. Clinical assessments were made after each week of treatment. Fiberoptic endoscopy and laboratory tests were performed before and after the treatment period. Thirty patients completed the study: 16 received diflunisal and 14 received ibuprofen. Similar improvements in pain, joint mobility, functional capacity, and joint swelling and tenderness were observed in both treatment groups. Transient, mild abdominal cramping was reported by two patients in each group; one patient receiving ibuprofen complained of transient dizziness. No patient withdrew from the study because of side effects. Follow-up endoscopy revealed slight (grade 1) changes in the gastric mucosa of two patients in each treatment group. An additional patient in the ibuprofen group had gastric erosions (grade 2) at the end of the study. Endoscopic changes were not correlated with symptoms. Diflunisal and ibuprofen were found to be similarly effective and well tolerated in the treatment of osteoarthritis. Their use may be associated with some gastrointestinal side effects even during short-term use.