AV nodal reciprocating tachycardia, arrhythmias associated w/ Wolff-Parkinson-White syndrome & similar conditions w/ accessory pathway. Paroxysmal atrial fibrillation in patients w/ disabling symptoms. Arrhythmias of recent onset will respond more readily. Symptomatic sustained ventricular tachycardia. Premature ventricular contractions &/or non-sustained ventricular tachycardia which are causing disabling symptoms, where these are resistant to other therapy or when other treatment has not been tolerated. Maintenance of normal rhythm following conversion by other means.
Supraventricular arrhythmias 50 mg bd, if required may be increased to a max of 300 mg daily. Ventricular arrhythmias Initially 100 mg bd, max: 400 mg/day. Recommended to progressively adjust to the lowest level which maintains arrhythmia control, after 3-5 days. Dosage may be reduced during long-term treatment.
Cardiac failure, patient w/ history of MI who has either asymptomatic ventricular ectopics or non-sustained ventricular tachycardia. Long standing atrial fibrillation w/ no attempt to convert to sinus rhythm, haemodynamically significant valvular heart disease. Sinus nodal dysfunction, atrial conduction defects, 2nd degree or greater AV block, bundle branch block or distal block unless pacing rescue available.
Most commonly, giddiness, dizziness, light-headedness, visual disturbances, nausea & vomiting. Proarrhythmia may occur in patients w/ structural heart disease &/or significant left ventricular impairment.
Drug Interactions
May cause rise in plasma digoxin. Possible additive negative inotropic effects of β-blockers & other cardiac depressants. Enzyme inducers enhance elimination. Reduce flecainide dosage by 50% when given w/ amiodarone.