Provided, among other things, is a method of treating or amelioratingpulmonary infection in a cystic fibrosis patient comprising pulmonaryadministration of an effective amount of a liposomal/complexed antfinfectiveto the patient, wherein the (i) administrated amount is 50 % or less of thecomparative free drug amount, or (ii) the dosing is once a day or less, or(iii) both.