Plasma Level Monitoring: The large majority of patients successfully treated with TAMBOCOR were found to have trough plasma levels between 0.2 and 1.0 ?g/mL.
The probability of adverse experiences, especially cardiac, may increase with higher trough plasma levels, especially when these exceed 1.0 ?g/mL.
Periodic monitoring of trough plasma levels may be useful in patient management.
Plasma level monitoring is required in patients with severe renal failure or severe hepatic disease, since elimination of flecainide from plasma may be markedly slower.Monitoring of plasma levels is strongly recommended in patients on concurrent amiodarone therapy and may also be helpful in patients with CHF and in patients with moderate renal disease.
In patients without structural heart disease, TAMBOCOR is indicated for the prevention of– paroxysmal supraventricular tachycardias (PSVT), including atrioventricular nodal reentrant tachycardia, atrioventricular reentrant tachycardia and other supraventricular tachycardias of unspecified mechanism associated with disabling symptoms– paroxysmal atrial fibrillation/flutter (PAF) associated with disabling symptomsTAMBOCOR is also indicated for the prevention of– documented ventricular arrhythmias, such assustained ventricular tachycardia (sustained VT), that in the judgment of the physician are life-threatening.Use of TAMBOCOR for the treatment of sustained VT, like other antiarrhythmics, should be initiated in the hospital.
The use of TAMBOCOR is not recommended in patients with less severe ventricular arrhythmias even if the patients are symptomatic.Because of the proarrhythmic effects of TAMBOCOR, its use should be reserved for patients in whom, in the opinion of the physician, the benefits of treatment outweigh the risks.TAMBOCOR should not be used in patients with recent myocardial infarction.
(See Boxed Warnings.)Use of TAMBOCOR in chronic atrial fibrillation has not been adequately studied and is not recommended.(See Boxed Warnings.)As is the case for other antiarrhythmic agents, there is no evidence from controlled trials that the use of TAMBOCOR favorably affects survival or the incidence of sudden death.
TAMBOCOR is contraindicated in patients with pre-existing second- or third-degree AV block, or with right bundle branch block when associated with a left hemiblock (bifascicular block), unless a pacemaker is present to sustain the cardiac rhythm should complete heart block occur.TAMBOCOR is also contraindicated in the presence of cardiogenic shock or known hypersensitivity to the drug.