Role of rectal formulations: enemas.

Clinical experience with mesalazine enemas in the treatment of ulcerative colitis is reviewed. After rectal administration, plasma mesalazine levels remain low, and 15% of the administered dose is recovered in the urine. Enemas containing 2 and 4 g of mesalazine have been shown to be effective, safe, and well tolerated by patients with mild and moderate ulcerative colitis. Patients who cannot tolerate sulfasalazine and patients who do not respond to other treatments have been successfully treated with mesalazine enemas. Suppositories of mesalazine are more suitable for patients with disease confined to the distal region of the colon, whereas mesalazine enemas should be used in patients with more extensive disease. Mesalazine enemas have also been used for maintenance therapy in ulcerative colitis.