Pharmacology of COX-2 inhibition in man: Antiinflammatory and analgesic effects of nimesulide

The clinical effects of cyclooxygenase 2 (COX-2) inhibitors in arthritis ar e being studied, particularly their potential for reducing risk from conven tional nonsteroidal antiinflammatory drugs (NSAIDs). COX-2 is expressed in the hypertrophied synovial tissue of patients with rheumatoid arthritis and studies show that it is responsible for protaglandin generation in the joi nt following surgical trauma. Further data suggest that prostaglandins play a role in pain perception by regulating opioid receptors and that removal of prostaglandins enhances opioid receptor signalling. Nimesulide has been found to exhibit a high degree of selectivity for COX-2 in vitro and in viv o. In patients undergoing thoracotomy, nimesulide provided better pain reli ef than opiates alone and reduced the need for opiates. Since nimesulide ha s no effect on platelet or gastric prostaglandin formation and induces less gastric and small bowel injury than conventional NSAIDs, it would have an advantage over NSAIDs in postoperative patients. While there are still a nu mber of outstanding questions on the safety of COX-2 selective inhibitors, they are proving to be as effective as NSAIDs in a variety of clinical cond itions and have been helpful in understanding the role of COX-2 in clinical disease. (C) 2001 Prous Science. All rights reserved.