The authors sought to evaluate renal tolerance for ioxaglate sodium meglumine used as a contrast agent in patients with chronic renal failure. Eight male patients (mean age, 55 years +/- 5) with chronic renal insufficiency (glomerular filtration rate less than 60 mL/min) who underwent diagnostic cardiac catheterization were enrolled. Renal clearance of inulin and rho-aminohippuric acid and urinary enzyme excretion were studied 1 day before and 1 day after administration of 167 mL +/- 43 of ioxaglate. None of the patients experienced any adverse reactions. All the patients had markedly depressed renal clearance values before angiography. Mean serum creatinine level, glomerular filtration rate, effective renal plasma flow, and urinary beta 2-microglobulin excretion were unaltered by angiography. After the procedure, only one patient had an increase in serum creatinine level of more than 10% (from 115 to 159 mumol/L [1.3 to 1.8 mg/dL]), with a decrease in glomerular filtration rate from 34 to 27 mL/min. In this patient, serum creatinine level and glomerular filtration rate normalized within 72 hours. Using accurate and sensitive renal function tests, the authors have shown that ioxaglate may be used safely in patients with chronic renal failure.