Patients ( n = 237 ) achieving normokalemia ( 3.5-5 .0 mEq/L ) were then randomized to receive zirconium cyclosilicate , 5 g ( n = 45 patients ) , 10 g ( n = 51 ) , or 15 g ( n = 56 ) , or placebo ( n = 85 ) daily for 28 days .