This happens to me since having UC, too. I always thought of it how dakotagirl explained it.
24 years old
Diagnosed with UC March 2007; yet to go into complete remission
Asacol 4 tablets 3x/day
Rowasa (generic) - nightly; Canasa (1,000 mg) in the morning
Nature's Way Primadophilus Reuteri 2/day; Chewable multivitamin; Metamucil; Viactiv