Berenbaum F.
Revue du rhumatisme (English ed.). 1998;65:634-640.

Cyclooxygenase-2 inhibitors, a new nonsteroidal anti-inflammatory, may offer improved efficacy and greater safety than conventional NSAIDs. The recent discovery of two isoforms of the COX enzyme has greatly increased the knowledge of prostaglandin synthesis. Traditional NSAIDs block the production of prostaglandins by inhibiting cyclooxygenase, which is responsible for the conversion of arachidonic acid to prostaglandins. Prostaglandins play a protective role, e.g. those produced in the stomach protect the gastric mucosa. In studies of patients with osteoarthritis and rheumatoid arthritis, celecoxib, a COX-2, given at 200 to 800 mg/day, was shown to be effective. Endoscopic examination of approximately 700 patients after 12 weeks of treatment, showed that the incidence of ulcers in those receiving celecoxib (6.1%) was similar to placebo (5%). However, in those receiving a conventional NSAID, ulcers were present in 26.3% of patients. The benefits of COX-2 SIs and how they compare with conventional NSAIDs can only be assessed once epidemiologic studies examining the occurrence rates of serious adverse events such as perforation, ulcers and bleeding are available. Until then, the use of COX-2s in the elderly and those with high ulcer risk should be avoided.