The effect of nimesulide on prostanoid formation

Nimesulide (4-nitro-2-phenoxy-methansulfonanilide) is a weak acidic (pKa = 6.50) nonsteroidal anti-inflammatory drug (NSAID) belonging to a new chemical class, the sulfonanilide derivatives, and does not contain the carboxylic group. It exhibits potent anti-inflammatory, analgesic and antipyretic activities. Although nimesulide is not a cyclo-oxygenase inhibitor in gastric tissues or bovine seminal vesicle microsomes, it inhibits prostaglandin synthesis in zymosan-stimulated murine macrophages in inflammatory exudate. Nimesulide significantly antagonises the immune formation of thromboxane B2 in lung tissue. It neither induces gastrointestinal lesions nor affects renal function in animal models.