['Oxidative stress is believed to have a role in contrast-induced nephropathy. Based on this assumption, several known antioxidants have been studied to assess their effect on nephropathy, especially N-acetylcysteine (NAC). However, its usefulness has yet to be confirmed.', 'We aimed to assess whether NAC has any protective effect on contrast-induced renal dysfunction, and whether NAC affects the parameters of oxidative stress in serum and urine.', 'Sixty patients with coronary artery disease, who presented for an elective percutaneous coronary intervention (PCI), were randomized into 2 groups in an age- and gender-matched fashion: one group received 600 mg intravenous NAC and the other did not. Before and 24 hours after the procedure, blood and urine samples were obtained to assess total oxidant capacity (TOC), total antioxidant capacity (TAC), oxidative stress index (OSI), and renal function.', 'Twenty-four hours after PCI, TOC and OSI levels were significantly increased and TAC levels significantly decreased, both in serum and urine. However, we did not observe any differences in oxidative parameters between patients who received NAC and those who did not. Multivariate analyses identified no protective effect of NAC on renal function, and no effect on oxidative parameters in either serum or urine.'] Does n-acetylcysteine fail to prevent renal dysfunction and oxidative stress after noniodine contrast media administration during percutaneous coronary interventions?