EFFECT OF INFUSION REGIME ON DOXORUBICIN PHARMACOKINETICS IN THE CAT

In the pharmacokinetic evaluation of a single doxorubicin dose calcula ted by body surface area (25 mg/m(2)) or body weight (1 mg/kg body wei ght) and given intravenously as a 10-, 15-, or 20-minute infusion, the rate of doxorubicin infusion (mg per minute per m(2) or mg per minute per kg) correlated positively with clearance and the distribution rat e constant a, and it inversely correlated with area under the plasma c oncentration versus time curve (AUC). These findings suggest that a sl ower infusion rate results in a greater AUC and longer distribution ph ase than a faster infusion rate and indicates the importance of normal izing dosage regimes by infusion rate rather than by infusion duration when considering dose-response phenomena in veterinary patients.