Radiographic contrast media is being used at an increasing rate for various diagnostic and therapeutic procedures. Renal failure following contrast administration for enhanced imaging has become a serious complication. Patients with underlying renal disorders have an increased incidence of Contrast Induced Nephropathy (CIN). CIN has been reported as the third most common cause of in-hospital renal failure after hypovolemia and post surgical renal insufficiency. Several factors increase the risk of CIN: preexisting renal dysfunction, volume and type of contrast agent employed, and lack of renal prophylaxis. CIN pathogenesis may be due to an injury to the renal cortex and outer medulla resulting from a decrease in blood flow, an osmotic effect, and/or direct toxicity to tubular cells by oxygen free radicals. N-acetylcysteine (NAC) is a cysteine analog and sulfur-containing agent, with strong antioxidant activity, which induces de novo synthesis of glutathione. NAC protection during the evolution of renal failure may be related to the ability to scavenge oxygen free radicals and/or improve endothelium-dependant vasodilation. There is no animal model that directly correlates with CIN, but the investigators have investigated nephrotoxicity and chemoprotection against cisplatin induced nephropathy which has a mechanism of action mediated through the generation of reactive intermediates in an animal model. NAC is potentially protective against cisplatin induced nephrotoxicity when administered at high intravenous (IV) doses (400 mg/kg) and at low intra-arterial (IA) doses (50mg/kg) down the descending aorta. This implies a safe dose-dependent effect of IV NAC and that lower doses can be used IA safely.