Nimesulide is a non-steroidal anti-inflammatory drug (NSAID) that is used primarily as an analgesic (pain reliever) and an anti-inflammatory agent. Its chemical name is N-(4-Nitro-2-phenoxyphenyl)methanesulfonamide and its CAS number is 51803-78-2.

Nimesulide works by inhibiting the synthesis of prostaglandins, which are responsible for inflammation and pain in the body. It is commonly used to treat conditions such as osteoarthritis, rheumatoid arthritis, and acute pain.

This drug is known for its relative selectivity and high potency in inhibiting the enzyme cyclooxygenase-2 (COX-2), which plays a crucial role in inflammation. By targeting COX-2, nimesulide reduces pain and inflammation without significantly affecting COX-1, an enzyme that helps protect the stomach lining.

Nimesulide is available in various forms including tablets, oral suspensions, and topical gels. It is usually taken orally and its effects typically start within 15-30 minutes. The drug is metabolized in the liver and excreted through u