I recently have been diagnosed with IBS w/ constipation. My gp put me on Nexium, Bentyl and peri colace. I have noticed that my stools are brown, but sometimes they are black, not all black. I was just wondering if any of the medications listed above could cause black stools? Also , I still have really bad bloating, how do you get rid of the bloating, or will I be bloated forever since I have IBS? Any info would be appreciated.