HIGHLIGHTS OF PRESCRIBING INFORMATION
These highlights do not include all the information needed to use RYTHMOL SR safely and effectively. See full prescribing information for RYTHMOL SR.
RYTHMOL SR (propafenone hydrochloride) Extended Release Capsules
Initial U.S. Approval: 1989
WARNING: MORTALITY
See full prescribing information for complete boxed warning
•An increased rate of death or reversed cardiac arrest rate was seen in patients treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in patients assigned to placebo. At present it is prudent to consider any IC antiarrhythmic to have a significant risk of provoking proarrythmic events in patients with structural heart disease.
•Given the lack of any evidence that these drugs improve survival, antiarrhythmic agents should generally be avoided in patients with non-life-threatening ventricular arrhythmias, even if the patients are experiencing unpleasant, but not life-threatening, symptoms or signs.
RECENT MAJOR CHANGES
Indications and Usage (1) 10/2010
Dosage and Administration (2) 10/2010
Warnings and Precautions, Drug Interactions: Simultaneous Use with Inhibitors of Cytochrome P450 2D6 and 3A4 (5.2) 10/2010
INDICATIONS AND USAGE
RYTHMOL SR is an antiarrhythmic indicated to prolong the time to recurrence of symptomatic atrial fibrillation (AF) in patients with episodic (most likely paroxysmal or persistent) AF who do not have structural heart disease. (1) (1)
Usage Considerations: (1)
•Use in patients with permanent atrial fibrillation or with atrial flutter or PSVT has not been eva luated. Do not use to control ventricular rate during atrial fibrillation. (1)
•In patients with with atrial fibrillation and atrial flutter, use RYTHMOL SR with drugs that increase the atrioventricular nodal refractory period. (1)
•The effect of propafenone on mortality has not been determined. (1)
DOSAGE AND ADMINISTRATION
•Initiate therapy with 225 mg given every 12 hours. (2)
•Dosage may be increased at a minimum of 5 day intervals to 325 mg every 12 hours and, if necessary, to 425 mg every 12 hours. (2)
•Dose reduction should be considered in patients with hepatic impairment, significant widening of the QRS complex, or second or third degree AV block. (2)
DOSAGE FORMS AND STRENGTHS
Capsules: 225 mg, 325 mg, 425 mg. (3) (3)
CONTRAINDICATIONS
•Heart failure (4)
•Cardiogenic shock (4)
•Sinoatrial, atrioventricular, and intraventricular disorders of impulse generation and/or conduction in the absence of pacemaker (4)
•Bradycardia (4)
•Marked hypotension (4)
•Bronchospastic disorders and severe obstructive pulmonary disease (4)
•Marked electrolyte imbalance (4)
WARNINGS AND PRECAUTIONS
•May cause new or worsened arrhythmias. eva luate patients via ECG prior to and during therapy. (5.1)
•Avoid simultaneous use of propafenone with both a cytochrome P450 2D6 inhibitor and a 3A4 inhibitor. (5.2)
•Avoid use with other antiarrhythmic agents or drugs that prolong the QT interval. (5.3)
•May provoke overt heart failure. (5.4)
•May cause dose-related first degree AV block or other conduction disturbances. Should not be given to patients with conduction defects in absence of a pacemaker. (5.5)
•May affect artificial pacemakers. Pacemakers sho