Enteric coated naproxen; a double blind trial comparing the tolerance of enteric coated and standard formulations.

Enteric coated naproxen (Nycopren) was compared with standard naproxen in a double blind comparative trial of 348 patients with either rheumatoid or osteoarthritis. There were slightly fewer gastric side effects and slightly fewer withdrawals because of side effects in the enteric coated naproxen group but the differences did not reach statistical significance. There was no significant difference in the efficacy of the two formulations. A satisfaction index was used to assess the therapeutic ratio with visual analogue scales assigned to both efficacy and side effects. The scale performed as intended and is worthy of further exploration.