Pain and inflammation.

The traditional "aspirin first" approach to the treatment of osteoarthritis and rheumatoid arthritis is undergoing serious reappraisal. Aspirin and acetaminophen are equipotent in their analgesic efficacy; however, aspirin is associated with a higher incidence of side effects. Acetaminophen should therefore be used as first-line therapy for the treatment of osteoarthritis since reduction of pain is the primary therapeutic objective. Analgesic doses of aspirin (up to 3,900 mg per day) do not produce an anti-inflammatory effect and thus are not beneficial in the treatment of rheumatoid arthritis. Only high doses of aspirin (4 to 6 g per day) used for a sustained period produce an anti-inflammatory effect. Since many patients with rheumatoid arthritis cannot tolerate long-term use of anti-inflammatory doses of aspirin, it may be preferable to initiate therapy with one of the newer nonsteroidal anti-inflammatory drugs.