[Are COX-2 inhibitors truly able to prevent NSAIDs-associated ulcer?]

Non-steroidal anti-inflammatory drugs(NSAIDs) have a potential to cause mucosal injury in the gastrointestinal tract. Inhibitions of cyclooxygenase, one of the targets of NSAIDs and direct cytotoxic effects of NSAIDs, are reported to be involved in NSAIDs-related mucosal damage. It is estimated that 15-30% of patients taking NSAIDs develop gastroduodenal ulcers, 2% of patients have life-threatening complications. Normal gastroduodenal mucosa expresses only COX-1, and it is reported that NSAIDs are more strongly inhibiting COX-1 are more harmful to gastroduodenal mucosa. Therefore, selective COX-2 inhibitors have been developed as safer NSAIDs than non-selective NSAIDs. Recent reports have, however, shown that COX-2 is expressing in gastroduodenal ulcers and H. pylori infection, suggesting that COX-2 plays an important role in mucosal healing. In this article, we discuss whether COX-2 selective inhibitors are able to prevent NSAIDs-associated ulceration.