Why does chemotherapy cause diarrhea?
Chemotherapy damages rapidly dividing cells. Cancer cells tend to divide rapidly and uncontrollably. However, some healthy cells also divide rapidly, such as those that line the interior of the digestive tract. Chemotherapy also damages these cells, leading to a disruption in the delicate fluid balance that they maintain. Specifically, absorption of fluid from the gastrointestinal (GI) tract back into the body is decreased and secretion of fluid and electrolytes in the stool is increased. This causes watery bowel movements, the definition of diarrhea.
