A review of 43 trials published prior to Dec 2013 suggests that taking probiotics may help irritable bowel syndrome and chronic idiopathic constipation.  The review shows that symptoms of irritable syndrome were 21% less likely to persist in patients using probiotics compared to those using nothing.  Probiotics were also found to provide beneficial effects on global irritable bowel syndrome, stomach pain, bloating, and flatulence in patients with irritable bowel syndrome.  In addition to having a benefitial effect on irritable bowel syndrome, probiotics as well as synbiotics also have beneficial effects on chronic idiopathic constipation.  (David Liu, PHD)Ford AC, Quigley EM, Lacy BE, Lembo AJ, Saito YA, Schiller LR, Soffer EE, Spiegel BM, Moayyedi P.  Efficacy of Prebiotics, Probiotics, and Synbiotics in Irritable Bowel Syndrome and Chronic Idiopathic Constipation: Systematic Review and Meta-analysis.  Am J Gastroenterol. 2014 Jul 29.