Ileus, meaning the obstruction of the small intestine, may also be referred to as bowel obstruction. Other synonyms for ileus include intestinal obstruction, blocked bowel, intestinal adhesion, and intestinal strangulation. The term paralytic ileus is used to describe a type of the condition that occurs when the muscles in the bowel become paralyzed, causing the contents to become blocked. Other types of ileus include mechanical ileus and functional ileus. Mechanical ileus is caused by a physical obstruction of the intestine, whereas functional ileus is often caused by injury or surgery to the bowel. Regardless of the synonyms used, ileus is a serious medical condition that requires immediate attention and treatment.