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Ileus !i-lE-us

(Paralytic Ileus; Adynamic Ileus)

by Parswa Ansari, MD

Ileus (paralytic ileus, adynamic ileus) is temporary absence of the normal contractile movements of the intestinal wall.

  • Abdominal surgery and drugs that interfere with the intestine’s movements are a common cause.

  • Bloating, vomiting, constipation, cramps, and loss of appetite occur.

  • The diagnosis is made by x-ray.

  • People are given nothing to eat or drink, and a thin suction tube is passed through the nose into the stomach.

Like an obstruction (blockage) of the intestines, ileus prevents the passage of intestinal contents. Unlike a mechanical obstruction, though, ileus rarely leads to rupture.

Ileus commonly occurs for 24 to 72 hours after abdominal surgery, particularly when the intestines have been manipulated. Drugs, especially opioid analgesics and anticholinergic drugs (see Anticholinergic: What Does It Mean?), are a common cause. Ileus may also be caused by an infection inside the abdomen, such as appendicitis or diverticulitis. Disorders outside the intestine, such as kidney failure, an underactive thyroid gland, or abnormal levels of blood electrolytes (low potassium levels or high calcium levels, for example), may cause ileus.

Symptoms and Diagnosis

The symptoms of ileus are abdominal bloating, nausea, vomiting, severe constipation, loss of appetite, and cramps.

A doctor hears few of the sounds normally made by a functioning intestine (bowel sounds) or none at all through a stethoscope. An x-ray of the abdomen shows bulging loops of intestine.


The buildup of gas and liquid caused by ileus must be relieved. Usually, a tube is passed through the nose into the stomach or small intestine, and suction is applied to relieve pressure and expansion (distention). The person is not allowed to eat or drink anything until the intestine functions normally (or until function returns). Fluids and electrolytes (such as sodium, chloride, and potassium) are given by vein (intravenously). Sometimes, if the problem involves mainly the large intestine, a tube is passed through the anus into the large intestine to relieve the pressure.