Flunoxaprofen is a chiral nonsteroidal anti-inflammatory drug (NSAID). It is an arylalkanoic acid derivative. Flunoxaprofen inhibits leukotriene rather than prostaglandin synthesis. Its potency was comparable with that of indomethacin and higher than that of acetyl salicylic acid, ibuprofen or phenylbutazone. The analgesic activity of flunoxaprofen, evaluated by the hot plate method and tail pinching in mice, was slightly lower than that of indomethacin but higher than that of acetyl salicylic acid and ibuprofen. Its adverse reactions profile is similar to the profiles of other NSAIDs, including gastrointestinal disturbances. Flunoxaprofen was withdrawn from clinical use because of concerns of potential hepatotoxicity.