PENTASA Sachet is used for the treatment of mild to moderate attacks of ulcerative colitis and to help maintain freedom from further attacks. Ulcerative colitis is an inflammatory bowel disease in which the lining of the intestine becomes inflamed and develops many tiny breaks in its surface (ulcers) which may bleed. PENTASA Sachet contains granules that slowly release the active ingredient (mesalazine). This helps reduce the inflammation and the painful symptoms.