Treatment of ulcerative colitis with olsalazine and sulphasalazine: efficacy and side-effects.

The effects of olsalazine were studied mainly in patients with ulcerative colitis who were intolerant to sulphasalazine, and for relapse prevention. A crossover design with sulphasalazine, 3 g/day, and olsalazine, 1.5 g/day, was applied to compare the side-effects of each drug and to evaluate their therapeutic efficacy. A total of 41 patients with mild or moderately severe left-sided colitis or proctitis were assigned to a randomized treatment schedule. Olsalazine and sulphasalazine were similar in their therapeutic efficacy. Twelve patients complained of adverse effects while on sulphasalazine and 4 patients during olsalazine treatment (p less than 0.05). It is concluded that olsalazine is a safe and effective drug for the treatment of mild or moderately severe ulcerative colitis, and is comparable to sulphasalazine, though with reduced side-effects.