Irritable bowel syndrome: dietary and pharmacological therapeutic options

In irritable bowel syndrome, the main objectives of the treatment are the relief of abdominal pain then the improvement of bowel disturbances. Spasmolytic agents, or clays remain routinely the first line pharmacological options. The efficacy of dietary recommandations is not validated in most of the cases while dietary fibers, mainly insoluble fibers, may even worsen abdominal discomfort. In C-IBS, osmotic laxatives or macrogol are effective to improve colonic transit while loperamide and also colestyramine can be prescribed to reduce the number of stools of D-IBS patients. When the first line treatment fails to improve symptoms, antidepressants (tricyclic rather than SSRs) can be prescribed at lower doses than that recommended for depression. In meta-analysis, the odds ratio for pain relief varies from 2 to 4 and strongly depends on the patient's compliance to the treatment. Probiotics, pregabalin and even antibiotics (i.e neomycin, metronidazole or rifaximin), are possible new therapeutic options. Few clinical trials suggest that ramosetron (a new 5HT3 antagonist), octreotide, melatonin, or lidocain could be also discussed in the future. A non pharmacological therapeutic approach has to be considered, particularly in patients with severe symptoms, in combination with pharmacological treatment. (C) 2009 Elsevier Masson SAS. All rights reserved.