Pharmacokinetic study of amiodarone in dogs

Abstract

Pharmacokinetic variables of Amiodarone were studied in six healthy dogs. Plasma levels of amiodarone and its metabolite, desethylamiodarone, were determinated by HPLC at different moments, after an i.v. administration as infusion of 5 mg/Kg in two minutes. A compartment model independent pharmacokinetic analysis program was used to evaluate plasma levels of amiodarone vs time. The following results were obtained: AUC: 9.95 ± 2.91 mg/mL/hr, b: 0.25 ± 0.27 L/hr, Cl: 8.82 ± 1.95 mL/min./Kg, TMR: 7.38 ± 1.52 hrs, t_1/2b 5.056 ± 4.5 hrs and Vd: 3.424 ± 2.3 L/Kg. Amiodarone pharmacokinetic disposition presented a rapid distribution and decrease from blood during the first 30 minutes after i.v. Then it was slowly eliminated. It is concluded that amiodarone is an alternative to be considered in cardiac pathology in dogs, since the pharmacokinetic parameters, similar to those of human volunteers, can contribute to determine the apropiate dose to be administered.