"I have diagnosed with small bowel bacterial overgrowth.  I had eaten at a restaurant last September and had gotten very sick from the food, and have had stomach problems since then; bloating and constipation.  The GI prescribed me Linzess a few days ago. I took first one yesterday and a few hours later I had such horrible, severe diarrhea.  My stomach cramped most of the day and was pretty nauseated to where all I felt comfortable eating was toast and Cream of Wheat.   Just took my second one, will see if that was a one time effect or if it&#039;ll happen again.  If it does, will not take any more as the diarrhea was so so severe that I&#039;d rather put up with the bloating and constipation than the severe diarrhea."