Irritable bowel syndrome pathophysiology

From Spruill WJ, Wade WE. Diarrhea, constipation and irritable bowel syndrome. In DiPiro JT, Talbert RL, Yee CC, et al, (eds.) Pharmacotherapy A Pathophysiologic Approach. 6th ed. New York McGraw-Hill, Inc 677-692, with permission. 

Irritable bowel syndrome (IBS) affects 10-22% of the general population (54) and results in high health care utilization (55). The pathophysiology is not clearly defined diet, psychological distress, infection, altered mucosal immunity, visceral hypersensitivity, intestinal dysmotility, and abnormal brain-gut interactions are potential mechanisms for this disorder (56). Treatment options vary and are generally selected based on the patient s primary symptom. 

Crowell MD. Role of serotonin in the pathophysiology of the irritable bowel syndrome. Br J Pharmacol 2004 141(8) 1285-1293. 

Irritable bowel syndrome is one of the most common gastrointestinal disorders, and is characterized by lower abdominal pain, disturbed defecation, and bloating. Many nongastrointestinal manifestations also exist with IBS. Recent studies have found that visceral hypersensitivity is a major culprit in the pathophysiology of the disease. 

Camilleri M, Lasch K, Zhou W. (2012) Irritable Bowel Syndrome Methods, Mechanisms, and Pathophysiology. The confluence of increased permeability, inflammation, and pain in irritable bowel syndrome. Am J Physiol Gastrointest Liver Physiol 303 G775-G785. 

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