What are the pharmacological properties, clinical actions, and adverse effects of amiodarone in treating arrhythmias?
Amiodarone is a highly effective antiarrhythmic with unique pharmacokinetics, but its clinical utility must be weighed against its significant potential for multiorgan toxicity.
Amiodarone Therapy. Amiodarone is a unique compound, with actions of all four antiarrhythmic drug classes. It has been used effectively to treat a broad range of ventricular and supraventricular arrhythmias. As a result of amiodarone's enormous volume of distribution and slow disposition kinetics, gradual accumulation occurs during maintenance dosing, and the drug's clinical action can be produced more rapidly with the use of an early loading period. Similarly, plasma concentrations and effects of amiodarone decrease slowly after drug discontinuation. There is a clinical impression that amiodarone is superior over other agents for a wide variety of arrhythmias, but this remains unproven. Because of uncertainty regarding amiodarone's efficacy compared to alternative therapies, and amiodarone's important potential for causing cardiac, pulmonary, hepatic, central nervous system, ocular, thyroid, and cutaneous adverse effects, amiodarone's precise role in antiarrhythmic therapy remains to be established. ( J Cardiovasc Electrophysiol, Vol. 3, pp. 266–280, June 1992 )
Nattel et al. (Mon,) studied this question.