Interactions between tambocor(flecainide) and Norvir soft gelatin (ritonavir)
flecainide and ritonavir (Major Drug-Drug)
CONTRAINDICATED: Coadministration with ritonavir may significantly increase the plasma concentrations of some antiarrhythmic agents such as amiodarone, bepridil, flecainide, propafenone, and quinidine. The proposed mechanism is ritonavir inhibition of CYP450 3A4 and/or 2D6, the isoenzymes responsible for the metabolic clearance of these agents. Although clinical data are lacking, the interaction could conceivably lead to serious and/or life-threatening reactions including QT interval prolongation and ventricular arrhythmias such as ventricular tachycardia and torsade de pointes.
MANAGEMENT: The use of ritonavir with amiodarone, bepridil, flecainide, propafenone, or quinidine is considered contraindicated.
