Comparison of the efficacy and safety of 1.5 compared with 3.0 g oral slow-release mesalazine (Pentasa) in the maintenance treatment of ulcerative colitis

Objective: To investigate a possible dose-effect relationship with two dosages of oral slow-release mesalazine in patients with quiescent ulcerative colitis. Method: One hundred and sixty-nine patients with ulcerative colitis in remission were treated with either 1.5 or 3.0 g/day mesalazine for 1 year or until relapse into active colitis. Results: Fewer of the 3.0 g dose group relapsed than of the 1.5 g dose group (33 compared with 46%). This difference failed to reach statistical significance (P = 0.057). A significant relationship between age and relapse rate was established. No dose-related adverse events were found. Three serious drug-related adverse events were, however, reported. All of the serious adverse reactions resolved after the medication was discontinued. Conclusion: There is a trend for high doses of oral mesalazine to be more effective in prevention of relapse of ulcerative colitis. These higher doses are not associated with a higher incidence of adverse reactions.