Irritable bowel syndrome (IBS) is a widespread functional disorder which is characterized by regularly repeated pains or discomfort in the abdominal area along with violation of the bowel without identifiable organic causes. Recently it has been shown, the trigger in IBS appearance turns out to be stress causing the emergence of excessive emotions. Under stressful conditions neuropeptides (substance P) activation occurs and contributes the inflammatory changes appearance of the mucous membrane of the colon with minimum character. Continuing attempts to produce the effective therapy scheme of IBS with prolonged action didn’t show the results in any current of disease. Due to the results, problem of search and unbiased assessment of a medication faces difficulties in the complication and the poor knowledge of IBS pathophysiology and high level of placebo effect in the group of patients. A new approach in IBS therapy is the use of medicine Kolofort, made by Materia Medika Holding company on the basis of antibodies to human factor in tumour necrosis α (anti-FTN- α), brain specific protein S-100 (anti-S100) and histamine (anti-H). Combination of the three active components allows to affect central and peripheral links in pathogenesis of bowel functional violations, including visceral hypersensitivity, facilitates the reduction of abdominal severity of pain syndrome and recovery of gastrointestinal tract motility. Preclinical and clinical research, made earlier, showed the effectiveness and safety of Kolofort and its components in treatment of gastrointestinal pathology of inflammatory and functional genesis, along with the cupping of somatoform disfunctions and psychoneurological disorders on the background of somatic and neurologic diseases. Many specialists are interested in the results of multicentre randomized clinical research, made with aim to show the clinical effectiveness and safety of Kolofort when treating patients with IBS under conditions of blind placebo-control.