Constipation: Advances in Diagnosis and Treatment.

IMPORTANCE: Chronic constipation accounts for at least 8 million annual visits to health care providers in the United States and is associated with large expenditures for diagnostic testing and prescription and nonprescription laxatives. OBSERVATIONS: Strong evidence for efficacy has been established for stimulant and osmotic laxatives, new intestinal secretogogues, and peripherally restricted μ-opiate receptor antagonists, the latter a major advance in the treatment of opioid-induced constipation (OIC). An algorithm provided to evaluate chronic idiopathic constipation (CIC) that is refractory to available laxatives focuses on the importance of defecation disorders and biofeedback therapies. When used appropriately, available stimulant laxatives such as senna and bisacodyl are both safe and effective when used long-term. There is a paucity of (and a strong desire for) studies that compare inexpensive laxatives with newer agents that work by other mechanisms. CONCLUSIONS AND RELEVANCE: The choice of treatment for CIC and OIC should be based on cost as well as efficacy. The small subgroup of patients who do not respond to currently available laxatives requires further evaluation at experienced centers that are capable of performing studies of defecation and colonic transit.