Fosrenol (Lantan) is used to reduce high blood phosphate levels in people on dialysis due to severe kidney disease. Dialysis removes some phosphate from your blood, but it is difficult to remove enough to keep phosphate levels in the body in balance. Reducing phosphate levels in the blood can help keep bones strong, prevent unsafe buildup of minerals in the body, and help reduce the risk of heart disease and stroke caused by high phosphate levels.