Constipation 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. 

Pathophysiologically, constipation generally results from disordered colonic transit or anorectal function as a result of a primary motility disturbance, certain drugs, or in association with a large number of systemic diseases that affect the gastrointestinal tract. Constipation from any cause may be exacerbated by chronic illnesses that lead to physical or mental impairment and result in inactivity or physical immobility. Additional contributing factors may include a lack of fiber in the diet, generalized muscle weakness, and possibly stress and anxiety. 

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