PROPAFENONE
(pro-pa'fen-one)
Rythmol
Classifications: cardiovascular agent; antiarrhythmic classic
Prototype: Flecainide
Pregnancy Category: C
|
150 mg, 225 mg, 300 mg tablets
Class IC antiarrhythmic drug with a direct stabilizing action on myocardial membranes. Reduces spontaneous automaticity.
Appropriate dose and concentration decreases rate of single and multiple PVCs. In addition, suppresses ventricular tachycardia.
Exerts a negative inotropic effect on the myocardium.
Ventricular arrhythmias.
Atrial tachyarrhythmias, reentrant arrhythmias, Wolff-Parkinson-White syndrome.
Uncontrolled CHF, cardiogenic shock, sinoatrial, AV or intraventricular disorders (e.g., sick sinus node syndrome, AV block)
without a pacemaker; bradycardia, marked hypotension; bronchospastic disorders; electrolyte imbalances; hypersensitivity to
propafenone; nonlife-threatening arrhythmias; chronic bronchitis, emphysema; lactation.
CHF, AV block; hepatic/renal impairment; older adult patients; pregnancy (category C). Safety and efficacy in children are
not established.
Ventricular Arrhythmias
Adult: PO Initiate with 150 mg q8h, may be increased at 3–4 d intervals (max: 300 mg q8h)
|
- Dosage increments gradually are usually made with older adults or those with previous extensive myocardial damage.
- Significant dose reduction is warranted with severe liver dysfunction. Consult physician.
- Store at 15°–30° C (59°–86° F).
CNS:
Blurred vision, dizziness, paresthesias, fatigue, somnolence, vertigo, headache. CV: Arrhythmias, ventricular tachycardia, hypotension, bundle branch block, AV block, complete heart block, sinus arrest, CHF. Hematologic: Leukopenia, granulocytopenia (both rare). GI: Nausea, abdominal discomfort, constipation, vomiting, dry mouth, taste alterations, cholestatic hepatitis. Skin: Rash.
Drug:
Amiodarone,
quinidine increases the levels and toxicity of propafenone. May increase levels and toxicity of tricyclic antidepressants, cyclosporine,
digoxin,
beta blockers, theophylline, and warfarin may increase levels of both propafenone and diltiazem.
Phenobarbital decreases levels of propafenone.
Absorption: Readily absorbed from GI tract. Peak: 3.5 h. Distribution: 97% protein bound, highest concentrations in the lung. Crosses placenta, distributed into breast milk. Metabolism: Extensively metabolized in the liver. Elimination: 18.5–38% of dose excreted in urine as metabolites. Half-Life: 5–8 h.
Assessment & Drug Effects
- Monitor cardiovascular status frequently (e.g., ECG, Holter monitor) to determine effectiveness of drug and development of
new or worsened arrhythmias.
- Monitor patients with preexisting CHF closely for worsening of this condition. Monitor for digoxin toxicity with concurrent
use, because drug may increase serum digoxin levels.
- Report development of second- or third-degree AV block or significant widening of the QRS complex. Dosage adjustment may be
warranted.
Patient & Family Education
- Report to physician any of following: Chest pain, palpitations, blurred or abnormal vision, dyspnea, or signs and symptoms
of infection.
- Be aware when taking concurrent warfarin of possible increase in plasma levels that increase bleeding risk. Report unusual
bleeding or bruising.
- Monitor radial pulse daily and report decreased heart rate or development of an abnormal heartbeat.
- Be aware of possibility of dizziness and need for caution with walking, especially in older adult or debilitated patients.
- Do not breast feed while taking this drug.
1%)
Canadian drug name; 
Prototype drug