Generic Name and Formulations:
Propafenone HCl 150mg, 225mg, 300mg; scored tabs.
Indications for RYTHMOL:
Documented life-threatening sustained ventricular arrhythmias. To prolong recurrence of disabling paroxysmal atrial fibrillation/flutter or paroxysmal supraventricular tachycardia in patients without structural heart disease.
Individualize. Initially 150mg every 8hrs. May increase at intervals of at least 3–4 days (longer for elderly or marked myocardial damage) to 225mg every 8hrs; max 300mg every 8hrs. Hepatic impairment: reduce dose by 20–30%.
Heart failure. Cardiogenic shock. SA, AV and intraventricular disorders of impulse generation or conduction (eg, sick sinus syndrome, AV block), unless paced. Known Brugada Syndrome. Bradycardia. Marked hypotension. Bronchospastic disorders. Marked electrolyte imbalance.
Significant proarrhythmic risk in structural heart disease. Avoid in patients with non-life-threatening ventricular arrhythmias. Monitor ECG, pacemakers before and during therapy. Discontinue if ECG changes are suggestive of Brugada Syndrome or if CHF worsens; reduce dose if 2nd- or 3rd- degree AV block or QRS widening occurs. Monitor for agranulocytosis. Hepatic or renal dysfunction. Elderly. Labor & delivery. Pregnancy (Cat.C). Nursing mothers: not recommended.
Class IC antiarrhythmic.
Local anesthetics may increase CNS effects. Avoid drugs that may prolong the QT interval (eg, antiarrhythmics, phenothiazines, cisapride, bepridil, tricyclic antidepressants, macrolides). Avoid concomitant quinidine, amiodarone. Potentiates β-blockers, warfarin, digoxin (consider reducing their doses when starting propafenone), desipramine, cyclosporine, theophylline. Antagonized by rifampin. Monitor and adjust dose with CYP2D6, CYP1A2, and CYP3A4 inhibitors.
Dizziness, palpitations, chest pain, dyspnea, taste disturbance, nausea, fatigue, anxiety, constipation, upper respiratory tract infection, edema, influenza, angina pectoris, atrial flutter, 1st degree AV block, heart failure, bradycardia, headache, blurred vision; new or exacerbated arrhythmias, conduction defects, elevated ANA titer, exacerbation of myasthenia gravis.