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What causes irritable bowel syndrome?
Last reviewed: 06.07.2025
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Irritable bowel syndrome is the result of a violation of biological, psychological and social adaptation of a person, the basis of formation lies in changes in visceral sensitivity and intestinal motor activity, persistent disturbances in the cooperation of the nervous and immune systems of the body.
The main links in the development of irritable bowel syndrome are considered to be:
- dysfunction of cholinergic and adrenergic nerves, imbalance of neurotransmitters and regulatory peptides (cholecystokinin, motilin, neurotensin), opioid peptides (enkephalins, endorphins, vasoactive intestinal peptide, serotonin, etc.);
- increased sensitivity of the smooth muscles of the colon to intestinal regulators;
- lability of the central nervous system, when the intestine plays the role of a target organ, realizing a violation of the regulation of the functions of visceral organs. The threshold of pain sensitivity changes, the susceptibility of the receptor apparatus of the intestine is disrupted.
The most severe forms of irritable bowel syndrome develop in children and adolescents who have experienced severe life shocks.
Suppression of the urge to defecate (lack of time in the morning, travel, shyness, discomfort in the toilet), leading to partial or complete loss of the physiological reflex of defecation, contributes to the development of irritable bowel syndrome.