Amiodarone in a newborn with ventricular tachycardia and an intracardiac tumor: adjusting the dose according to an individualized dosing regimen.

We report the successful management of recurrent ventricular tachycardias in a newborn suffering from an intracardiac tumor. Amiodarone was the only agent able to control the tachycardias and did so as long as an individually titrated plasma concentration above 0.8 mu mol/L was maintained. Because no therapeutic plasma concentration has been defined in children and no kinetic studies are available in this population, we optimized the dosing regimen based on a computer simulation, taking into account the pharmacokinetic parameters of the patient and the individual concentration-effect relation.