Douglas A. Drossman, MD: It's a disorder, a functional GI disorder where there's abdominal pain primarily, with some alteration of bowel habit. Some people can have what's called diarrhea predominant, where you have abdominal pain. Often you might get the pain after a meal or when under stress. And then you might have to run to the bathroom and have diarrhea and very often, uh at least based on the criteria, the pain could be relieved after a bowel movement. Other people might have more of a constipation pattern, where they uh have infrequent bowel movements, are straining to have a bowel movement and this is associated with increased pain. And some people can actually have diarrhea one time and constipation another time. Then there can be other associated symptoms, like bloating, nausea and a variety of other conditions.