Asacol is proven to treat flare-ups Asacol is proven to treat mild to moderate flare-ups of ulcerative colitis. In animal studies rats, dogs the kidney is the principal target organ for toxicity. Tilt the bottle slightly towards the back, then squeeze it slowly to discharge the contents. Stop using Asacol and call your doctor at once if you have any of these serious side effects: severe stomach pain, cramping, fever, headache, and bloody diarrhea. You may notice the empty shell from this medicine in your stool. In six-week clinical study of flare-ups, Asacol was evaluated for its ability to reduce ulcerative colitis symptoms, including rectal bleeding, number of bowel movements, and abdominal pain. Because many of these comprar asacol pagar bacalao events were reported voluntarily from population of unknown size, estimates of frequency cannot be made.