Lanthanum prevents the body from absorbing phosphate, allowing it to be removed from the body. lanthanum carbonate is used to lower phosphate levels in patients with end stage kidney disease. high levels of phosphate can make it hard for your body to absorb calcium, which can cause serious medical problems.it is a phosphate binder indicated to reduce serum phosphate in patients with end stage renal disease (esrd).management of elevated serum phosphorus levels in end stage renal disease patients usually includes all of the following: reduction in dietary intake of phosphate, removal of phosphate by dialysis and reduction of intestinal phosphate absorption with phosphate binders.