Rectal 5-aminosalicylic acid for maintenance of remission in ulcerative colitis.

5-Aminosalicylic acid (5-ASA) is a first-line therapy for inducing and maintaining remission of mild and moderately active ulcerative colitis (UC). When the proximal margin of inflammation is distal to the splenic flexure, 5-ASA therapy can be delivered as a rectal suppository, foam or liquid enema.