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.