Aminosalicylates are of proven benefit in maintaining medically induced remissions of both ulcerative colitis and Crohn's disease. Even rectal 5-aminosalicylic acid has been found to be useful in maintaining long-term remissions of distal ulcerative colitis. Particularly noteworthy is the demonstrated efficacy of oral mesalamine in reducing recurrence rates of Crohn's disease following ileocecal resection, if introduced within the first few weeks after surgery. In all cases, the efficacy of the aminosalicylates is dose related, with little benefit demonstrable, at least in Crohn's disease, at oral doses < 2 g/day. In contrast to aminosalicylates, corticosteroids and cyclosporine are better suited to the induction of rapid remissions of acute disease than to the maintenance of long-term remissions. Antimetabolites, especially azathioprine and 6-mercaptopurine, are highly beneficial and relatively safe for long-term steroid-sparing therapy in both ulcerative colitis and Crohn's disease, at least for those patients whose initial remissions have already been induced by these agents.