These act by inhibiting the formation of PROSTAGLANDINS, which are mediators of INFLAMMATION. They act both as ANALGESICS to relieve pain, and as inhibitors of inflammation. Aspirin is a classic example of such a compound. Newer compounds have been synthesised with the aim of producing fewer and less severe side-effects. They are sometimes preferred to aspirin for the treatment of conditions such as RHEUMATOID ARTHRITIS, OSTEOARTHRITIS, sprains, strains and sports injuries. Their main side-effects are gastrointestinal: DYSPEPSIA, gastric ulcers and gastric haemorrhage may result (see STOMACH, DISEASES OF) because prostaglandins are necessary for the production of the mucous protective coat in the stomach. When the production of prostaglandin is inhibited, the protection of the stomach is compromised.

Ibuprofen is one of the first choices in this group of drugs, as it combines good efficacy with a low incidence of side-effects and administration is only required twice daily. Other drugs in this series include diclofenac, fenbufen, fenclofenac, fenoprofen, feprazone, flurbiprofen, indomethacin, indoprofen, ketoprofen, ketorolac, naproxen, piroxicam, sulindac, tiaprofenic acid and tolmetin.