Radiographic contrast agents can cause acute renal failure that may be due to acute tubular necrosis (ATN). We prospectively studied 45 patients with risk factors for ATN who were undergoing computed tomography with three nonionic contrast agents (ioversolo, iobitridolo and iodixanolo). Patients were randomly assigned either to receive preventive management (0.45% saline intravenously, before and after administration of the contrast agent; mannitol 20% 250 mL i.v. 60 min before and 60 min after the contrast agent; furosemide 80 mg i.v. 30 min before the contrast agent; dopamine 3 g/Kg/min i.v. after administration of the contrast agent for 24 hours) or to receive placebo. Prophylactic management prevents the reduction in renal function induced by ioversolo, iobitridolo and iodixanolo, three noninonic contrast agents in patients with risk factors for ATN.