A fecal impaction is a large lump of dry, hard stool that remains stuck in the rectum. It is most often seen in patients with long-term constipation.
Impaction of the bowels
Causes, incidence, and risk factors
Constipation is when you are not passing stool as often as you normally do. Your stool becomes hard and dry, and it is difficult to pass.
Fecal impaction is often seen in people who have had constipation for a long time and have been using laxatives. Impaction is even more likely when the laxatives are stopped suddenly. The muscles of the intestines forget how to move stool or feces on their own.
Persons at risk for chronic constipation and fecal impaction include those who:
Do not move around much and spend most of their time in a chair or bed
Have diseases of the brain or nervous system that damage the nerves that go to the muscles of the intestines
Certain drugs slow the passage of stool through the bowels:
Anticholinergics, which affect the interaction between nerves and muscles of the bowel
Medicines used to treat diarrhea, if they are taken too often
Tell your health care provider if you are experiencing chronic diarrhea or fecal incontinence after a long period of constipation. Also notify your health care provider if you are experiencing any of the following symptoms:
Sudden constipation with abdominal cramps, and an inability to pass gas or stool. In this case, do not take any laxatives. Call your health care provider immediately.
Very thin, pencil-like stools
Lembo AJ, Ullman SP. Constipation. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier;2010:chap 18.
Nelson H. Diseases of the rectum and anus. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 148.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; George F Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.