Irritable bowel syndrome (IBS) is a common disorder with widespread prevalence. Due to its heterogeneous pathogenesis, efficacious treatments are lacking. The few medications that are effective for treating global IBS symptoms have either been withdrawn or restricted due to detrimental side effects; thus, safe and effective alternatives are urgently needed. Increasing data have revealed that inflammatory changes may play a role in the development of IBS, and probiotics, commensal organisms with inherent health benefits, may alter that milieu. Although their exact mechanisms of action remain elusive, it is clear that the beneficial properties inherent to each probiotic species are strain specific. Bifidobacterium infantis 35624 ( B infantis 35624; Bifantis, The Procter & Gamble Company, Cincinnati, OH), is a probiotic with unique abilities to reduce intestinal inflammation. Two randomized, controlled trials have validated its efficacy for treating both individual and global IBS symptoms without evidence to suggest an increase in adverse events. B. infantis 35624 appears safe and effective for the treatment of IBS.