Differential effect of type I and type II diabetes on antipyrine disposition in man.

As the influence of diabetes on drug metabolism in patients is controversial, a study was performed to assess antipyrine (AP) disposition in controlled Type I and Type II diabetics and 2 age- and sex-matched control groups. In Type I diabetics, the half-life of AP was significantly reduced from 12.0 (controls) to 7.9 h, and the volume of distribution (V) was lowered from 733 to 569 ml.kg-1. The resulting plasma clearance and cumulative urinary excretion of AP and its metabolites over 24 h did not differ from controls. In Type II diabetics, the AP half-life (14.5 h) and V (568 ml.kg-1) did not differ from their age- and sex-matched controls (11.1 h and 643 ml.kg-1, respectively), but the plasma clearance of AP was significantly reduced by 30%, and urinary excretion was significantly reduced to 44% of controls. The differential effects of Types I and II diabetes on AP metabolism may explain, at least in part, the controversial data in the literature.