The intestine is made up of the small intestine and the large intestine (colon). The small intestine runs from the stomach to the large intestine. The colon runs from the end of the small intestine to the anus. The intestine absorbs nutrients and water from the diet.

Obstruction of the intestine occurs when food and water cannot pass through the intestine. The area of intestine nearest to the obstruction becomes dilated and non-functioning. If the obstruction is not relieved, it can lead to intestinal gangrene and perforation.

The most common causes of intestinal obstruction in adults are adhesions, hernias, and colon cancer. Adhesions are scars that form between loops of intestine, usually caused by prior surgery, which causes such scar formation. Hernias are areas of weakness in the abdominal wall, through which loops of intestine can slip and become trapped. Colon cancer is one of the most common forms of cancer. While each reason for intestinal obstruction requires a different treatment, all intestinal obstructions are potentially life-threatening.

In most cases, surgery is necessary. While the patient is deep asleep and pain-free (general anesthesia), an incision is made in the midline of the abdomen. In the case of adhesions, the adhesion is removed, thus relieving the obstruction. In the case of a hernia, the hernia is repaired. If colon cancer is present, cancerous areas are removed, which also relieves the obstruction.

In all cases, the intestine involved in the obstruction is examined. If any parts of the intestine look unhealthy from lack of blood flow during the period of obstruction, they are removed and the healthy ends are reconnected. A patient's recovery depends on several factors, including the cause of the intestinal obstruction and the length of time prior to relief of the obstruction.