It has been widely recognized that the elderly shows an increased prevalence of cardiac arrhythmias. Moreover, the elderly population presents a number of problems to the clinician prescribing antiarrhythmics, such as drug accumulation, low compliance and proarrhythmias. In this article, we discussed age-related changes of the pharmacokinetics and the pharmacodynamics of antiarrhythmics with reference to proarrhythmia in the elderly. Age-dependent decrease of renal creatinine clearance plays an important role in the pharmacokinetics in the elderly. Age-related changes of pharmacodynamics of antiarrhythmics have not been evaluated extensively. Our results concerning the effect of class 1a drug on filtered QRS width on signal-averaged ECG, demonstrated age-related accentuation of class 1 action. In terms of non-pharmacologic treatment, physiological pacing is useful especially on elderly patients. The indications for catheter ablation and implantable cardiverter-defibrillators for the elderly should be established in detail.