CausesBy Mayo Clinic staff
CLICK TO ENLARGE
Constipation most commonly occurs when waste or stool moves too slowly through the digestive tract, causing it to become hard and dry.
Normally, the waste products of digestion (stool) are propelled through your intestines by muscle contractions. In the large intestine (colon), most of the water and salt in this waste mixture are reabsorbed because they're essential for many of your body's functions.
However, when there is not enough fluid or fiber-rich food in your diet — or if the colon's muscle contractions are slow — the stool hardens, dries and passes through your colon too slowly. This is the root cause of constipation.
You may also experience constipation if the muscles you use to move your bowels aren't properly coordinated. This problem is called pelvic floor dysfunction (anismus), and it causes you to strain with most bowel movements — even soft ones.
A number of factors can cause an intestinal slowdown, including:
- Inadequate fluid intake or dehydration
- Inadequate amounts of fiber in your diet
- Ignoring the urge to have a bowel movement or delaying until later
- Lack of physical activity (especially in older adults)
- Irritable bowel syndrome
- Changes in lifestyle or routine, including pregnancy, aging and travel
- Frequent use or misuse of laxatives
- Specific diseases, such as stroke, diabetes, thyroid disease and Parkinson's disease
- Problems with the colon and rectum, such as intestinal obstruction or diverticulosis
- Certain medications, including pain medications, diuretics and those used to treat Parkinson's disease, high blood pressure and depression
- Hormonal disturbances, such as an underactive thyroid gland
- Anal fissures and hemorrhoids, which can produce a spasm of the anal sphincter muscle
- Loss of body salts through vomiting or diarrhea
- Injuries to the spinal cord, which can affect the nerves that lead to and from the intestine
In rare cases, constipation may signal more-serious medical conditions, such as colorectal cancer, hormonal disturbances or autoimmune diseases. In children, constipation might indicate Hirschsprung's disease, a congenital condition that results from missing nerve cells in the colon.
Children may also become constipated if they are afraid of or unwilling to use the toilet. Older children may ignore or forget to attend to bowel movements.
- Constipation. National Digestive Diseases Clearinghouse. http://digestive.niddk.nih.gov/ddiseases/pubs/constipation/. Accessed Dec. 16, 2010.
- Lembo AJ, et al. Constipation. In: Feldman M, et al. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa.: Saunders Elsevier; 2010. http://www.mdconsult.com/books/about.do?eid=4-u1.0-B978-1-4160-6189-2..X0001-7--TOP&isbn=978-1-4160-6189-2&about=true&uniqId=229935664-2192. Accessed Dec. 16, 2010.
- Wald A. Etiology and evaluation of chronic constipation in adults. http://www.uptodate.com/home/index.html. Accessed Dec. 16, 2010.
- Wald A. Management of chronic constipation in adults. http://www.uptodate.com/home/index.html. Accessed Dec. 16, 2010.
- Constipation. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merckmanuals.com/professional/sec02/ch008/ch008b.html . Accessed Dec. 16, 2010.
- Hass DJ. Complementary and alternative medicine. In: Feldman M, et al. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa.: Saunders Elsevier; 2010. http://www.mdconsult.com/books/about.do?eid=4-u1.0-B978-1-4160-6189-2..X0001-7--TOP&isbn=978-1-4160-6189-2&about=true&uniqId=229935664-2192. Accessed Dec. 16, 2010.
- How much physical activity do adults need? Centers for Disease Control and Prevention. http://www.cdc.gov/physicalactivity/everyone/guidelines/adults.html. Accessed Dec. 16, 2010.
- Picco MF (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 20, 2010.