Expired CME Article
Irritable Bowel Syndrome: A Practical Review
Abstract
The epidemiology and current understanding of the pathophysiology of irritable bowel syndrome is reviewed, beginning with a historical perspective. The roles of genetics, environment, allergy, infection and inflammation, bacterial overgrowth, hormones and motility abnormalities are discussed. Using the current evidence-based literature, the practical approach of diagnosis and treatment is outlined, including traditional modalities and newer therapeutic agents such as serotonin modulators.
Key Points
* Irritable bowel syndrome (IBS) is a functional bowel disorder in which abdominal pain or discomfort is associated with defecation or changes in bowel habits, with symptoms present for at least 12 weeks out of the previous 12 months.
* IBS is a common disorder, more commonly present in women, that accounts for 28% of the visits to gastroenterologist.
* Diagnosis is based on the clinical symptoms, keeping the investigations to a minimum.
* Symptomatic treatment depends on the predominant symptom: antidiarrheal drugs in diarrhea-predominant IBS, fiber and laxatives in constipation-predominant IBS, antispasmodics for abdominal pain.
* If the initial treatment fails to improve symptoms or if changes suggestive of organic disease appear, more investigations/referral may be necessary.
* Newer drugs to be used are antidepressants, 5-HT3 antagonists (alosetron) for diarrhea-predominant IBS, 5-HT4 agonists (tegaserod) for constipation-predominant IBS.
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