Acute renal failure is one of the side effects while using intravenous immunoglobulins. This complication is also observed with iodinated contrast media. Herein, we describe a patient with acute renal failure who received intravenous immunoglobulins and iodinated contrast media concomitantly. Both drugs are responsible for osmotic nephrosis. The same effect on renal cells may explain a synergistic effect on renal function.