Clinical Pearls for Irritable Bowel Syndrome Management of the Diarrhea-Predominant Subtype

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder that is characterized by the presence of abdominal pain or discomfort and is subtyped by the predominant stool symptoms of constipation, diarrhea, or mixed constipation and diarrhea. The diagnosis of IBS was once considered to be one of exclusion, but data now show that exhaustive tests provide very limited diagnostic yield. Instead, the symptom-based Rome criteria can be used to make a confident determination of IBS. For patients diagnosed with IBS, pharmacological decisions are based on the underlying disturbances such as abdominal pain, bowel symptoms, and urgency; how the condition affects quality of life; and symptom severity. Traditionally, treatment of IBS has focused on one or two individual symptoms rather than syndrome relief; however, emerging evidence on newer targeted treatment options is drawing clinical attention. Targeted treatment will require ongoing evaluation of disease severity, as current data show that severe IBS is more common than previously thought and severity influences treatment choices. This article reviews the disease state of IBS, answers questions about the condition, and discusses the evidence supporting current management options.