Flecainide Acetate

A to Z Drug Facts

 Action Produces a dose-related decrease in intracardiac conduction in all parts of the heart; also has local anesthetic activity.

 Indications Prevention of paroxysmal atrial fibrillation/flutter (PAF) associated with disabling symptoms; paroxysmal supraventricular tachycardias (PSVTs); prevention of documented life-threatening ventricular arrhythmias.

 Contraindications Preexisting second-or third-degree AV block; right bundle branch block when associated with a left hemiblock (unless a pacemaker is present); recent MI; presence of cardiogenic shock.

 Route/Dosage

PSVT, PAF

ADULTS: Initial dose: PO 50 mg q 12 hr, increasing by 50 mg bid q 4 days until efficacy is achieved. Maximum for PSVT: 300 mg/day.

Sustained Ventricular Tachycardia

ADULTS: Initial dose: PO 100 mg q 12 hr, increasing to 150 mg bid if needed. Maximum: 400 mg/day.

 Interactions

Amiodarone: Increased flecainide plasma levels. Cimetidine: Increased bioavailability and clearance of flecainide. Digoxin: Increased digoxin plasma levels. Propranolol: Levels of either drug may be increased; additive negative inotropic effects. Smoking: Increased dosage may be required. Urinary acidifiers: Effects of flecainide may be decreased. Urinary alkalinizers: Effects of flecainide may be increased.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Arrhythmias; palpitations; chest pain; tachycardia; hypotension. CNS: Dizziness; insomnia; syncope; anxiety; ataxia; depression; hypoesthesia; malaise; paresthesia; vertigo; lightheadedness; faintness; headache; fatigue; asthenia; tremor; increased sweating; somnolence. DERM: Rash; flushing. EENT: Visual disturbances; tinnitus; diplopia. GI: Nausea; constipation; abdominal pain; vomiting; diarrhea; anorexia. OTHER: Fever; dyspnea.

 Precautions

Pregnancy: Category C. Lactation: Excreted in breast milk. Children: Safety and efficacy in children < 18 yr not established. Mortality: In clinical trials, an excessive mortality rate was noted. Cardiovascular disorders: Use with caution in patients with arrhythmias, CHF, cardiomyopathy, low ejection fraction, and conduction abnormalities. Flecainide slows cardiac conduction in most patients to produce a dose-related increase in PR, QRS and QT intervals. Use with extreme caution in patients with sick sinus syndrome, because drug may cause sinus bradycardia, sinus pause, or sinus arrest. Flecainide increases endocardial pacing thresholds and may suppress ventricular escape rhythms in patients with pacemakers. Hepatic impairment: Do not use in patients with hepatic impairment unless benefits outweigh risks. Potassium imbalances: Effect of flecainide may be altered in patients with hypokalemia or hyperkalemia; condition should be corrected before administering flecainide.

 Administration/Storage

• May be given with or without food.
• Store at room temperature in tightly closed, light-resistant container.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies. Note recent MI.
• If patient has sustained ventricular tachycardia, initiate therapy in hospital and monitor rhythm.
• Ensure that baseline liver and kidney function tests have been obtained before beginning therapy.
• Ensure that baseline potassium level has been obtained before beginning therapy, and monitor at regular intervals.
• Review baseline ECG to assess for second- or third-degree heart block or sick sinus syndrome. Monitor rhythm closely while initiating therapy.
• Measure PR, QRS and QT intervals before beginning therapy and monitor closely while initiating therapy.
• Monitor urinary pH while initiating therapy because pH alters drug elimination.
• In patient with pacemakers, determine pacing threshold before beginning therapy, at 1 wk, and at regular intervals thereafter while receiving drug.
• Assess BP before initiating therapy and at regular intervals during treatment.
• Monitor trough plasma levels of drug at regular intervals.
• Monitor renal patients closely for toxic effects and assess plasma levels frequently.
• If patient is also receiving digoxin, monitor digoxin levels closely.
• Assess patient for signs and symptoms of CHF.
• If patient develops potassium imbalances, increased PR, QRS and QT intervals, chest pain, hypotension, or signs of CHF, notify physician immediately.

 Patient/Family Education

• Emphasize importance of taking drug as prescribed and not missing or adjusting dosage.
• Teach patient how to take pulse and instruct to do so daily.
• Instruct patient to report the following symptoms to physician: Diarrhea, abdominal pain, palpitations, chest pain, tachycardia, hypotension, dizziness, asthenia, tremor, tinnitus, somnolence, visual disturbances, fever, dyspnea, or rash.
• Instruct patient in measuring and recording weight on daily basis.
• Offer family instruction in basic life support.
• Advise patient that drug may cause dizziness or drowsiness and to use caution while driving or performing other tasks requiring mental alertness.

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Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts