Correlation between gastric irritancy and anti-inflammatory activity of non-steroidal anti-inflammatory drugs.

Gastric irritancies and anti-inflammatory potencies of 25 commercially available non-steroidal anti-inflammatory drugs (NSAIDs) have been measured in the rat. When irritancy is measured as the dose required to produce a specified level of gastric mucosal damage, it is found that irritancy increases with anti-inflammatory potency. However, when irritancy is measured as the level of gastric mucosal damage at the anti-inflammatory ED50 (which is a clinically realistic measure) then irritancy decreases as anti-inflammatory potency increases. Hence it should be possible to design high-potency, low-irritancy NSAIDs.