Contrast-induced nephropathy (CIN) is the third cause of acquired acute renal dysfunction. The risk of developing a contrast media (CM)-induced nephropathy depends on their different physicochemical properties. The iso-osmolality of third generation CM lowers the incidence of CM-related renal dysfunction. The tubular effect of CM and the hemodynamic changes induced by CM in the renal medulla are thought to be the main mechanisms of CIN. The percentage of patients at risk has been estimated to range between 3.5 and 15.5% depending on the presence of a preexisting impaired renal function, diabetes mellitus, congestive heart failure, and hypertension and on the volume of contrast used. Currently, only hydration is a generally accepted method of reducing the risk of CIN, and further trials are needed to prove the effectiveness of other potential prophylactic treatments. Alternatives to ordinary CM, such as carbon dioxide or gadolinium chelates, can be used in patients at high risk of CIN undergoing peripheral diagnostic or interventional procedures, thus reducing the occurrence of CIN.