In order to investigate the role of sucralfate in active ulcerative colitis, 60 patients were randomized to receive either sucralfate enemas (20 g/100 mi) or methylprednisolone enemas (20 mg/100 mi). The enemas were administered twice daily for one week, and then once daily for three weeks. Clinical evaluation was documented at entry and at two weeks and four weeks. The sigmoidoscopic appearance of the rectal mucosa was scored, and rectal biopsies taken at entry and at four weeks. Results indicated similar reduction in diarrhea and rectal bleeding at two weeks and at four weeks. Sigmoidoscopy demonstrated similar significant improvement in the macroscopic appearance of the rectal mucosa in both groups (8.28 to 6.20 in sucralfate group, P < 0.02; and 8.72 to 6.36 in the methylprednisolone treated group, P < 0.04). Histologic assessment, likewise, showed similar improvements in the two groups. This study indicates that sucralfate enemas may be useful in the treatment of ulcerative proctosigmoiditis.