Paroxetine flecainide, interactions

Potentially clinically significant interactions include the tendency for fluvoxamine to increase circulating concentrations of oxidatively metabolized benzodiazepines, clozapine, theophylline, and warfarin. Sertraline and fluoxetine can increase levels of benzodiazepines, clozapine, and warfarin. Paroxetine increases levels of clozapine, theophylline, and warfarin. Fluoxetine also potentiates tricyclic antidepressants and some class 1C antiarrhythmics with a narrow therapeutic index (including encainide, flecainide, and propafenone). Nefazodone potentiates benzodiazepines other than lorazepam and oxazepam. 

Tsao YY, Gugger JJ. Delirium in a patient with toxic flecainide plasma concentrations the role of a pharmacokinetic drug interaction with paroxetine. Ann Pharmacother 2009 43(7) 1366-9. 

Drug-drug interactions Flecainide Fleca-inide, a class 1C antidysrhythmic agent, is metabolized by CYP2D6. In a study of the interaction of the CYP2D6 10 allele and paroxetine in an open crossover study in healthy Korean subjects, paroxetine significantly increased the AUC of flecainide and... 

The effects of CYP2D6 genetic polymorphisms on the pharmacokinetics of a single oral dose of flecainide and on the extent of its interaction with paroxetine have been investigated in an open study in 21 healthy Korean volunteers [69 ]. The AUC, terminal half-life, and mean residence time increased significantly after paroxetine in those with the CYP2D6 10 allele, which is common among Asians. 

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