ABSTRACT
Phenazone pharmacokinetics as an index of hepatic microsomal enzyme activity was studied in 31 patients with Hodgkin's disease, 11 patients with non-Hodgkin's lymphoma and 52 healthy volunteers. The mean phenazone half-life (t0.5) was significantly shorter in patients with Hodgkin's disease (8.002 +/- 2.775 h) and in patients with non-Hodgkin's lymphoma (8.775 +/- 2.440 h) than in healthy persons (11.351 +/- 3.706 h). In patients with Hodgkin's disease and in patients with non-Hodgkin's lymphoma mean elimination rate constant (Kel) (0.101 +/- 0.050 h-1; 0.086 +/- 0.028 h-1) and mean metabolic clearance rate (MCR) (70.464 +/- 50.347 ml/min; 71.621 +/- 21.448 ml/min) differed statistically significantly from the same parameters in control group, where K was 0.067 +/- 0.021 h-1 and MCR 49.361 +/- 18.167 ml/min. Treatment with antineoplastic drugs inhibited phenazone elimination. No correlations were found between the phenazone pharmacokinetics parameters and routine laboratory tests of liver function. Since many drugs are metabolized by cytochrome P-450, similar to phenazone, it is likely that their elimination in patients with Hodgkin's disease and in patients with non-Hodgkin's lymphoma will be also changed. This should be considered in selection of their dosage.
