Overview of Constipation

Constipation is characterized by a decrease in the frequency of bowel movements, or by fewer than three bowel movements per week. Constipation often results in hard, dry stools that are small in size and difficult to pass, painful bowel movements, and other symptoms (e.g., bloating).

Constipation is common, and the condition affects most people at some point during their lifetimes. Children, women, and people over the age of 65 experience constipation more often.

During digestion, food moves through the gastrointestinal (GI) tract and nutrients and water are absorbed. Waste material from this process (stool or feces) is eventually eliminated from the body through the anus. Constipation occurs when the colon (also called the large bowel or large intestine) absorbs too much water, or when food moves too slowly through the colon, resulting in dry, hard stool.

Irregular bowel habits, childbirth, and surgery increase the risk for constipation. Disruptions in daily routines (e.g., travel) also can increase the risk. Other risk factors and conditions that can cause constipation include the following:

  • Anxiety, fear, excessive worry
  • Cancer (e.g., colorectal cancer, anal cancer)
  • Certain medications (e.g., narcotic pain relievers, calcium channel blockers, antidepressants) and supplements (e.g., iron, calcium)
  • Diabetes
  • Excessive use of laxatives
  • Improper diet (e.g., inadequate dietary fiber, inadequate fluid intake)
  • Intestinal obstruction or conditions (e.g., irritable bowel syndrome, diverticular disease)
  • Muscle disorders (e.g., weakness, spasticity)
  • Neurological disorders (e.g., stroke, multiple sclerosis [MS], Parkinson's disease, spinal cord injury)
  • Pregnancy
  • Sedentary life style, lack of exercise
  • Systemic diseases (e.g., lupus, scleroderma)

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 28 Feb 2008

Last Modified: 08 Sep 2015