Background: Irritable bowel syndrome (IBS) is a complex syndrome that is difficult to manage. Here we present the evidence supporting medication treatments for specific IBS symptoms, discuss evidence-based management of IBS with medications including dose regimens and adverse effects and review progress on research for new IBS treatments. Summary: Currently, there is evidence to support improvements in specific IBS symptoms following treatment with loperamide, psyllium, bran, lubiprostone, linaclotide, amitriptyline, trimipramine, desipramine, citalopram, fluoxetine, paroxetine, dicyclomine, peppermint oil, rifaximin, ketotifen, pregabalin, gabapentin and octreotide and there are many new medications being investigated for the treatment of IBS. Key Message: Of the medications with demonstrated improvements for IBS symptoms, rifaximin, lubiprostone, linaclotide, fiber supplementation and peppermint oil have the most reliable evidence supporting their use for the treatment of IBS. Onset of efficacy for the various medications has been noted to be as early as 6 days after initiation; however, the efficacy of most medications was not assessed prospectively at predefined periods. Additional studies of currently available and new medications are ongoing and are needed to better define their place in therapy and expand therapeutic options for the treatment of IBS. The most promising new medications for IBS include a variety of novel pharmacologic approaches, most notably the dual μ-opioid receptor agonist and δ-opioid antagonist, JNJ-27018966.

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