Long-term clinical assessment of naproxen on rheumatoid arthritis patients and 51-Cr gastrointestinal bleeding on volunteers.

64 patients with rheumatoid arthritis (R.A.) entered the trial: 40 of them still remain on medication; 28 have so far completed 2 years; 23, 3 years; 12, 4 years using D-2-(6'-methoxy-2'-naphthyl)-propionic acid (naproxen) as the principal anti-inflammatory agent. Tolerance has been good: side effects or complaints, when reported, were mild and transient in nature. Close monitoring of a range of biochemical values by sequential laboratory studies has not revealed naproxen to have many adverse effects. After two years of daily continuous naproxen administration, 19 volunteer patients were subjected to a short-term double-blind cross-over placebo experiment. The results were in favor of a continued therapeutic efficacy of naproxen. The possible gastrointestinal bleeding found in the majority of anti-inflammatory drugs has been studied on 12 volunteers using 51-Cr. Naproxen exhibited a mean G.I. blood loss comparable to placebo or to physiological blood loss in normal volunteers. The conclusion drawn is that naproxen shows a good therapeutic index.