FLECAINIDE

(fle-kay'nide)

Tambocor
Classifications: antiarrhythmic, class ic;
Therapeutic: antiarrhythmic, class ic
Pregnancy Category: C

Availability

50 mg, 100 mg, 150 mg tablets

Action

Local (membrane) anesthetic and antiarrhythmic with electrophysiologic properties similar to other class IC antiarrhythmic drugs. Slows conduction velocity throughout myocardial conduction system, increases ventricular refractoriness.

Therapeutic Effect

Is an effective suppressant of PVCs and a variety of atrial and ventricular arrhythmias.

Uses

Life-threatening ventricular arrhythmias.

Unlabeled Uses

Atrial tachycardia and other arrhythmias unresponsive to standard agents (e.g., quinidine), Wolff-Parkinson-White syndrome, and recurrent ventricular tachycardias.

Contraindications

Hypersensitivity to flecainide; preexisting second- or third-degree AV block, right bundle branch block when associated with a left hemiblock unless a pacemaker is present; cardiogenic shock, significant hepatic impairment; CHF, acute MI; QT prolongation syndromes; electrolyte imbalances; pregnancy (category C).

Cautious Use

Atrial fibrillation; cardiac disease; elderly; sick sinus syndrome, renal impairment; children and infants.

Route & Dosage

Life-Threatening Ventricular Arrhythmias
Adult: PO 100 mg q12h, may increase by 50 mg b.i.d. q4d (max: 400 mg/d)
Child: PO 1–3 mg/kg/d in 3 divided doses (max: 8 mg/kg/d)

Administration

Oral

Do not increase dosage more frequently than every 4 d.
Store in tightly covered, light-resistant containers at 15°–30° C (59°–86° F) unless otherwise directed.

Adverse Effects (≥1%)

CNS: Dizziness, headache, light-headedness, unsteadiness, paresthesias, fatigue. CV: Arrhythmias, chest pain, worsening of CHF. Special Senses: Blurred vision, difficulty in focusing, spots before eyes. GI: Nausea, constipation, change in taste perception. Body as a Whole: Dyspnea, fever, edema.

Interactions

Drug: Cimetidine may increase flecainide levels; may increase digoxin levels 15–25%; beta blockers may have additive negative inotropic effects.

Pharmacokinetics

Absorption: Readily from GI tract. Peak: 2–3 h. Distribution: Crosses placenta; distributed into breast milk. Metabolism: In liver. Elimination: Mainly in urine. Half-Life: 7–22 h.

Nursing Implications

Assessment & Drug Effects

Correct preexisting hypokalemia or hyperkalemia before treatment is initiated.
Note: ECG monitoring, including Holter monitor for ambulating patients, is essential because of the possibility of drug-induced arrhythmias.
Determine pacing threshold for patients with pacemakers before initiation of therapy, after 1 wk of therapy, and at regular intervals thereafter.
Monitor plasma level recommended, especially in patients with severe CHF or renal failure because drug elimination may be delayed in these patients.
Note: Effective trough plasma levels are between 0.7–1 mcg/mL. The probability of adverse reactions increases when trough levels exceed 1 mcg/mL.
Attempt dosage reduction with caution after arrhythmia is controlled.

Patient & Family Education

Note: It is VERY important to take this drug at the prescribed times.
Report visual disturbances to physician.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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