Efficacy and gastroduodenal safety of a fixed combination of diclofenac and misoprostol in the treatment of arthritis.

Non-steroidal anti-inflammatory drugs (NSAIDs) are an effective therapy for the management of arthritis, but their use is restricted by the risk of gastrointestinal complications from NSAID-induced ulceration. The elderly, in particular, are vulnerable to such damage and complications. Misoprostol is the only cytoprotective drug found to be effective in the prevention of both gastric and duodenal ulcers associated with NSAIDs. A fixed-combination of diclofenac 50 mg/misoprostol 200 micrograms has been evaluated for efficacy and safety in the treatment of arthritis. Pharmacokinetic studies of the fixed combination have found that no drug-drug interaction occurs between misoprostol and diclofenac after either single or multiple doses, and the bioavailability of misoprostol and diclofenac are comparable with that of misoprostol and diclofenac given alone. This fixed combination was found to be equivalent to other NSAIDs in the control of symptoms and other parameters of arthritis. The fixed combination was generally well tolerated, although the occurrence of abdominal pain and diarrhoea was slightly more frequent than with other NSAIDs. This contrasts with a 2- to 3-fold reduction in the rate of gastroduodenal damage with the fixed combination compared with the rate associated with other NSAIDs. These results indicate that the diclofenac 50 mg/misoprostol 200 micrograms combination should be considered in preference to other NSAIDs when treating patients at risk of ulcer complications.