Pharmacokinetic evaluation of a sustained-release compounded procainamide preparation after 24-h (acute) administration in normal dogs

Abstract

IntroductionThe objective of the present study was to evaluate the pharmacokinetics of a compounded sustained-release procainamide formulation in normal dogs. AnimalsSix healthy, purpose-bred mixed-breed dogs participated in the study. MethodsIn phase I, two dogs were administered oral procainamide (30 mg/kg), and plasma was obtained to determine plasma concentration ranges and duration. In phase II, six dogs were administered procainamide (30 mg/kg by mouth every 12 hours) to determine the pharmacokinetics of sustained-release procainamide. Serum procainamide concentration was determined using an immunochemistry assay. ResultsNo adverse clinical effects were noted in any of the dogs studied. The average maximum serum concentration, average serum concentration, and average minimum serum concentration were 10.17, 7.13, and 3.07 μg/mL, respectively. The average time over a 12-h period during which procainamide concentration exceeded 12 μg/mL was 2.35 h, was between 4 and 12 μg/mL was 7.19 h, and was less than 4 μg/mL was 2.46 h. The average times at maximum concentration and minimum concentration were 18.67 and 12.25 h, respectively. ConclusionsAdministration of sustained-release procainamide twice daily achieved targeted plasma concentrations in most dogs. Evaluation of serum trough concentrations should be considered owing to interanimal variability to confirm that serum concentrations are within the reported therapeutic range for an individual patient.