- IBS with constipation. This comes with stomach pain and discomfort, bloating, abnormally delayed or infrequent bowel movement, or lumpy/hard stool.
- IBS with diarrhea. This comes with stomach pain and discomfort, an urgent need to move your bowels, abnormally frequent bowel movements, or loose/watery stool.
- IBS with mixed bowel habits (constipation and diarrhea).
There are about an equal number of people with IBS in each category. There is also evidence that most people with IBS will alternate between types over time.
This all makes it difficult for researchers to find a single drug treatment that will relieve all the symptoms of IBS. Different medications work for IBS with constipation and for IBS with diarrhea. Doctors will usually tailor an individual treatment regimen for people who have IBS with alternating symptoms.
"They should not take something for their constipation on their own, and then when they get diarrhea, take something for their diarrhea, and go back and forth," he says. "That can actually exacerbate the problem."