Nimesulide is a non-steroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties and a specific mode of action. Nimesulide is a sulphonanilide analogue; it is not related to conventional NSAIDs, which usually present a carboxyl or hydroxyl functional group.

Nimesulide is proved safe and effective in the symptomatic treatment of a wide range of inflammatory and painful conditions, including osteoarthritis, extra-articular disorders, pain and primary dysmenorrhoea. To date, more than 450 million patients treated since the first introduction of nimesulide on the market in Italy in 1985.

Nimesulide appears to exert its therapeutic effects through a variety of mechanisms:
- Preferential Cyclooxygenase-2 inhibition at its origin (gene Expression)
- Reduced generation of superoxide anions by stimulated polymorphonuclear leucocytes
- Inhibition of platelet aggregation factor synthesis by activated cells
- Nimesulide induces production of nitric oxide.
- Scavenger of inactivation of alpha 1-protease inhibitor
- Inhibition of histamine release
- Inhibition of protein kinase C through inhibition of phosphodiesterase type IV
- Reduced degradation of cartilage matrix through inhibition of metalloprotease synthesis
- Potent inhibition of induced platelet aggregation
- Prevention of bradykinin/cytokine induced hyperalgesia of nerves (inhibiting release of TNF-alpha).

The drug reduces superoxide anion generation by activated neutrophils without influencing their phagocytic or chemotactic responsiveness and inhibits the leucocyte respiratory burst through inhibition of phosphodiesterase (PDE) type IV, the principal enzyme responsible for the degradation of leucocyte cAMP. Also, Nimesulide protects chondrocytes, the cells that in normal conditions produces cartilage. 

The oral recommended dose of Nimesulide in adults is 100mg taken twice daily.

Nimesulide has been developed and licensed out by Helsinn Healthcare SA, Switzerland, which acquired the exclusive world-wide rights for the drug in 1976. Nimesulide is currently marketed in around 50 countries world-wide under different brand names, and it is among the most prescribed NSAIDs.

In more than 18 years of marketing experience nimesulide has proved safe and effective in the symptomatic treatment of a wide range of conditions, including osteoarthritis, painful extra-articular disorders such as tendonitis and bursitis, acute painful inflammatory states of different aetiology such as respiratory tract inflammation, post traumatic inflammation, odontostomatology and dental surgery, post-operative pain and primary dysmenorrhoea.

The drug is among the most prescribed NSAIDs in the world and over 200 clinical trials, involving more than 90,000 patients have also been conducted to assess its efficacy and safety. Many tolerability and post-marketing surveillance studies performed with nimesulide also support the high tolerability of this drug.