The pharmacological approach is the corner-stone of therapy for arrhythmia because it is non-invasive, convenient and widely available. However, the indications for antiarrhythmic therapy in general, as well as the indications for drug therapy as opposed to non-pharmacological therapeutic methods, are far from clearly defined. Among the existing antiarrhythmic drugs, clear reduction of mortality due to arrhythmia has been shown definitively only with beta-blocking agents and possibly with amiodarone.