Phenazone metabolism in patients with liver disease

Phenazone metabolism was studied in 14 patients with liver disease and six normal volunteers. The plasma and renal clearance of phenazone and the 4-hydrozyphenazone excretion in urine was significantly decreased in the patients with liver disease. The urinary excretion of 4-hydroxyphenazone was significantly correlated to the plasma clearance of phenazone (r= + 0.95, P less than 0.001), to quantitative liver function as measured by the galactose elimination capacity (r= + 0.95, P less than 0.001), and to the prothrombin values (r= + 0.82, P less than 0.001). The determination of the 4-hydroxyphenazone excretion in urine may be used as an easy and non-invasive test of quantitative liver function.