CHF and arrhythmias:
Indications for TAMBOCOR:
Documented, life-threatening ventricular arrhythmias. Paroxysmal supraventricular tachycardias (PSVT), paroxysmal atrial fibrillation/flutter (PAF) in patients without structural heart disease.
Sustained ventricular tachycardia: Initiate in hospital; initially 100mg every 12 hrs; may increase by 50mg twice daily at 4 day intervals; max 400mg/day. PSVT or PAF: 50mg every 12 hrs; may increase by 50mg twice daily at 4 day intervals; max 300mg daily. CrCl ≤35mL/min per 1.73m2: Initially 100mg once daily or 50mg every 12hrs.
<18yrs: not established.
2nd- or 3rd-degree AV block or right bundle branch block associated with left hemiblock, unless paced. Cardiogenic shock. Recent MI.
Mortality. Ventricular pro-arrhythmic effects in patients with atrial fibrillation/flutter.
Verify benefits outweigh risks; see full labeling. Increased risk of pro-arrhythmic effects. Chronic atrial fibrillation: not recommended. History of CHF or myocardial dysfunction. Sick sinus syndrome. Pacemaker patients. Correct potassium imbalances before use. Severe renal or hepatic impairment, concomitant amiodarone or reduced myocardial function: monitor plasma level. Discontinue if heart block occurs unless paced. Discontinue if liver dysfunction, blood dyscrasias occur. Pregnancy (Cat.C). Nursing mothers: not recommended.
Class IC antiarrhythmic.
Increased digoxin toxicity. May potentiate negative inotropic effects of β-blockers. Potentiated by cimetidine. Antagonized by phenytoin, phenobarbital, carbamazepine. Avoid disopyramide, verapamil, nifedipine, diltiazem, other negative inotropics. ½ dose when given with amiodarone.
Dizziness, visual disturbances, dyspnea, headache, fatigue, palpitations, chest pain, asthenia, tremor, edema, GI upset, new or exacerbated arrhythmias, heart failure, cardiac arrest, conduction defects.