Pharmacokinetics of antiarrhythmic drugs.

A knowledge of the determinants of the plasma concentrations of antiarrhythmic drugs is important because variation in plasma levels is often greater than the desired therapeutic range. The basic principles of pharmacokinetics are outlined and their application to the design of dosage regimens described. These principles are illustrated in a review of the pharmacokinetics of lidocaine and its congeners, procainamide and its active metabolite (N-acetylprocainamide), quindine, disopyramide, phenytoin and propranolol, with particular emphasis of the factors that contribute to altered disposition.