Markal is used as a nutritional supplement to treat high blood phosphate levels in patients undergoing dialysis due to chronic kidney disease. The active ingredient in this medicine is calcium acetate, which is an essential mineral for many body functions, especially in bone formation and maintenance. Calcium is also linked to other minerals such as phosphate, which helps remove it from the body. Calcium acetate works to bind phosphate in the food you eat, which leads to getting rid of phosphate and preventing its absorption in the body. Therefore, Markal is used to control blood phosphate levels in patients with kidney failure.