Meloxicam is a new nonsteroidal anti-inflammatory drug (NSAID) developed for the treatment of rheumatoid arthritis and osteoarthritis. It has greater in vitro and in vivo inhibitory action against the inducible isoform of cyclo-oxygenase (COX-2), which is implicated in the inflammatory response, than against the constitutive form of this enzyme (COX-1), inhibition of which is associated with gastric, renal and other adverse effects. It has anti-inflammatory effects similar to or better than those of other NSAIDs in animal models, and a greater therapeutic ratio (ulcerogenic potential:efficacy in adjuvant arthritis). In healthy volunteers meloxicam 7.5 or 15 mg caused less gastrointestinal mucosal damage on endoscopy than piroxicam 20 mg, with a significant difference between meloxicam 7.5 mg and piroxicam. In comparative clinical trials, meloxicam was at least as effective as piroxicam and naproxen in patients with rheumatoid arthritis, and diclofenac and piroxicam in patients with osteoarthritis. Meloxicam was at least as well tolerated as piroxicam, diclofenac or naproxen overall but had improved gastrointestinal tolerability compared with these agents.