Gastrointestinal tract losses Abnormal GI potassium losses occur in all of the following: Chronic diarrhea, including chronic laxative abuse and bowel diversion Clay (bentonite) ingestion, which binds potassium and greatly decreases absorption Rarely, villous adenoma of the colon, which causes massive potassium secretion Protracted vomiting or gastric suction (which removes volume and hydrochloric acid) causes renal potassium losses due to metabolic alkalosis and stimulation of aldosterone due to volume depletion; aldosterone and metabolic alkalosis both cause the kidneys to excrete potassium.