Comparison of delayed release 5 aminosalicyclic acid (mesazaline) and sulphalazine in the treatment of mild to moderate ulcerative colitis relapse

Abstract

Oral formulations of 5-aminosalicyclic acid (mesalazine) appear less toxic than sulphasalazine. We have therefore compared sulphasalazine, low dose mesalazine and high dose mesalazine in the treatment of mild to moderate relapse of ulcerative colitis. Sixty one patients (32 men, aged 20-78 years) were randomly allocated to sulphasalazine 2 g daily, mesalazine 800 mg daily, or msalazine 2.4 g daily in a double blind, double dummy, four week trial. Groups were comparable for age, sex, extent of disease, and pretrial sulphasalzine intake. Four patients were unable to complete the study because of treatment failure (two taking sulphasalazine and two high dose mesalazine). A further two patients taking sulphasalazine developed side effect necessitating withdrawal. Within treatment comparisons revealed significant improvement of: sigmoidoscopic grade in the sulphasalazine group; rectal bleeding, sigmoidoscopic and histological grade in the low dose mesalazine group; stool frequency, rectal and sigmoidoscopic grade in the high dose mesalazine group. Greater improvement in rectal bleeding (p < 0.05) and sigmoidoscopic appearances (p < 0.05) occurred in patients taking high dose mesalazine than in those taking sulphasalazine. In two patients taking high dose mesalazine minor rises of plasma creatinine concentrations occurred, suggesting the need to monitor renal function.