Mesalamine affects a substance in the body that causes inflammation, tissue damage, and diarrhea. Mesalamine is used to treat ulcerative colitis, proctitis, and proctosigmoiditis. Mesalamine is also used to prevent the symptoms of ulcerative colitis from recurring. Mesalamine may also be used for other purposes.
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using mesalamine and call your doctor at once if you have any of these serious side effects: severe stomach pain, cramping, fever, headache, and bloody diarrhea.