Propafenone hydrochloride is indicated to: prolong the time to recurrence of paroxysmal atrial fibrillation/flutter associated with disabling symptoms in patients without structural heart disease. prolong the time to recurrence of paroxysmal supraventricular tachycardia associated with disabling symptoms in patients without structural heart disease. treat documented ventricular arrhythmias, such as sustained ventricular tachycardia that, in the judgment of the physician, are life-threatening. Initiate treatment in the hospital. Usage Considerations: The use of propafenone hydrochloride tablets in patients with permanent atrial fibrillation or in patients exclusively with atrial flutter or PSVT has not been evaluated. Do not use propafenone hydrochloride tablets to control ventricular rate during AF. Some patients with atrial flutter treated with propafenone have developed 1:1 conduction, producing an increase in ventricular rate. Concomitant treatment with drugs that increase the functional atrioventricular nodal refractory period is recommended. The use of propafenone hydrochloride tablets in patients with chronic atrial fibrillation has not been evaluated. Because of the proarrhythmic effects of propafenone hydrochloride, its use with lesser ventricular arrhythmias is not recommended, even if patients are symptomatic, and any use of the drug should be reserved for patients in whom, in the opinion of the physician, the potential benefits outweigh the risks. The effect of propafenone on mortality has not been determined. Propafenone hydrochloride is an antiarrhythmic indicated to: prolong the time to recurrence of symptomatic atrial fibrillation in patients with episodic AF who do not have structural heart disease. prolong the time to recurrence of paroxysmal supraventricular tachycardia associated with disabling symptoms in patients who do not have structural heart disease. treat documented life-threatening ventricular arrhythmias. Usage Considerations: Use in patients with permanent atrial fibrillation or with atrial flutter or PSVT has not been evaluated. Do not use to control ventricular rate during atrial fibrillation. In patients with atrial fibrillation and atrial flutter, use propafenone hydrochloride with drugs that increase the atrioventricular nodal refractory period. Because of proarrhythmic effects, use with lesser ventricular arrhythmias is not recommended, even if patients are symptomatic. The effect of propafenone on mortality has not been determined.