Ibuprofen is a new, mild analgesic agent that may be useful in the symptomatic treatment of rheumatoid arthritis and osteoarthritis. Results of clinical studies have shown that its beneficial effects in these conditions are comparable, but not superior, to those of aspirin. However, at recommended doses it has less anti-inflammatory effect than aspirin. Its usefulness as an analgesic in the treatment of other types of pain and as an antipyretic has not yet been established. Ibuprofen causes fewer adverse effects on the gastrointestinal system, including occult bleeding, than aspirin. Serious adverse reactions have not been reported. Thus, ibuprofen may be acceptable for use in patients who cannot tolerate aspirin or other antirheumatic drugs. (JAMA 233:364-365, 1975)