Irritable Bowel Syndrome (IBS)
Overview
Plain-Language Overview
Irritable Bowel Syndrome (IBS) is a common disorder that affects the large intestine, causing symptoms like abdominal pain, bloating, and changes in bowel habits such as diarrhea or constipation. It is a chronic condition that impacts how the gut functions but does not cause permanent damage to the intestines. The exact cause is unknown, but it involves problems with how the brain and gut communicate, leading to abnormal muscle contractions and heightened sensitivity. People with IBS often experience discomfort that can interfere with daily activities. The condition is diagnosed based on symptoms since there are no specific tests for it.
Clinical Definition
Irritable Bowel Syndrome (IBS) is a functional gastrointestinal disorder characterized by chronic or recurrent abdominal pain associated with altered bowel habits in the absence of detectable organic disease. The pathophysiology involves visceral hypersensitivity, dysregulation of the brain-gut axis, abnormal intestinal motility, and psychosocial factors. IBS is classified into subtypes based on predominant stool pattern: IBS with diarrhea (IBS-D), constipation (IBS-C), mixed (IBS-M), or unclassified. It is a diagnosis of exclusion after ruling out other causes such as inflammatory bowel disease or infections. IBS significantly impacts quality of life and healthcare utilization but does not increase the risk of serious gastrointestinal diseases.