Two double-blind, randomised studies were conducted to compare the efficacy and tolerability of nimesulide (200 mg/day) with those of placebo or bromeline (240 mg/day). Treatments were administered orally to patients of either sex (aged 19 to 70 years) with acute infection and inflammation of the urogenital tract, and were given concomitantly with antimicrobial therapy for approximately 9 days. In both studies, a clinically significant improvement in symptoms, leading to complete remission, was achieved in most patients treated with nimesulide. Furthermore, treatment with nimesulide resulted in a more rapid improvement in symptoms and complete remission in a greater number of patients than did treatment with bromeline. Both nimesulide and bromeline were well tolerated.