of contrast-induced nephropathy and hospital-acquired renal failure. Contrast-induced nephropathy development is associated with longer hospital stay, increase in both short- and long-term morbidity and mortality, in addition to greater health care costs. The pathogenesis of contrast-induced nephropathy has not yet been fully explained in detail; however it is clear that the root concept is medullary hypoxia-induced renal tubular damage. Chronic kidney disease and diabetes mellitus are the two most important intrinsic predisposing factors to contrast-induced nephropathy. As no treatment can specifically target contrast-induced nephropathy, the main goal for clinicians is prevention of the disease. While the best approach for achieving this goal is still controversial, optimization of the patients' circulating volume remains the only proven strategy to date. As contrast-induced nephropathy is a potentially preventable clinical condition, its better understanding will lead to better prevention of this disease. Hereby, we aimed to discuss contrast-induced nephropathy from 7 different aspects in clinical practice: 1] clinical aspect, 2] prevalence, 3] pathophysiology, 4] contrast agents and renal cell apoptosis, 5] different contrast media, 6] prevention, and 7] treatment