ibuprofen, nonsteroidal anti-inflammatory drug (NSAID) that reduces pain, fever, and inflammation. Along with naproxen and ketoprofen, ibuprofen belongs to the propionic acid class of NSAIDs. It was first made available in 1967. Like other NSAIDs, it acts by inhibiting the body's production of prostaglandins. Available over the counter in a variety of preparations (e.g., Advil, Motrin, Nuprin), it is commonly used to treat rheumatoid arthritis, gout, and painful menstruation. Side effects include rash, alteration of platelet function and bleeding, and intestinal upset, which can lead to gastritis. Like other NSAIDS, it appears to have no potential for abuse or physical dependence. It should not be used by those who are allergic to aspirin.

Analgesic, one of the NSAIDs, especially effective against minor pain, fever, and inflammation. It works by inhibiting prostaglandin synthesis. It may irritate the gastrointestinal tract and should not be taken by anyone who has an allergy to aspirin or takes anticoagulants. Brand names include Advil, Motrin, and Nuprin. Seealso acetaminophen.

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