Flecainide

300 interactions 706 cited references

Also sold as: Tambocor®

About Flecainide

Flecainide is an antiarrhythmic medication used to prevent certain life-threatening irregular heartbeats. Read the full Flecainide drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Aug 9, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Pimozide Ritonavir Mesoridazine Piperaquine Nirmatrelvir Mavorixafor

18 Contraindicated 270 Major 11 Moderate 1 Minor

All (300) Contraindicated (18) Major (270) Moderate (11) Minor (1)

Major

Flecainide Risperidone Perseris An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Selpercatinib Retevmo Increased risk of QT interval prolongation Details Flecainide Sematilide An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Sertindole An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Sevoflurane Petrem Increased risk of QT interval prolongation Details Flecainide Simeprevir Olysio® Increased exposure to the antiarrhythmic agent Details Flecainide Siponimod Mayzent An increased risk of QT interval prolongation Details Flecainide Sodium Phosphate OsmoPrep An increased risk of QT interval prolongation Details Flecainide Sodium Phosphate, Dibasic An increased risk of QT interval prolongation Details Flecainide Sodium Phosphate, Monobasic An increased risk of QT interval prolongation Details Flecainide Solifenacin Vesicare An increased risk of QT interval prolongation Details Flecainide Sorafenib Nexavar An increased risk of QT interval prolongation Details Flecainide Sotalol Betapace Increased risk of QT interval prolongation or prolonged refractoriness Details Flecainide Spiramycin An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Sulfamethoxazole Sustain An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Sulpiride An increased risk of QT interval prolongation Details Flecainide Sultopride An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Sunitinib Sutent An increased risk of QT interval prolongation Details Flecainide Tacrolimus Astagraf An increased risk of QT interval prolongation Details Flecainide Taletrectinib Ibtrozi Increased risk of QT interval prolongation and torsade de pointes Details Flecainide Tamoxifen Nolvadex® An increased risk of QT interval prolongation Details Flecainide Tedisamil An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Telaprevir Increased flecainide plasma concentrations Details Flecainide Telavancin Vibativ An increased risk of QT interval prolongation Details Flecainide Telithromycin An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Tetrabenazine Xenazine An increased risk of QT interval prolongation and torsade de pointes Details Flecainide Tocilizumab Actemra Reduced CYP2D6 substrate exposure and reduced efficacy of CYP2D6 substrate Details Flecainide Toremifene Fareston An increased risk of QT interval prolongation, ventricular tachycardia or an increased risk of torsade de pointes Details Flecainide Tramadol ConZip Increased traMADol exposure and reduced exposure of the active metabolite Details Flecainide Trazodone Raldesy An increased risk of QT interval prolongation and an increased risk of cardiac arrythmia Details Flecainide Trichlormethiazide Increased risk of electrolyte imbalance and subsequent cardiotoxicity Details Flecainide Triclabendazole Egaten An increased risk of QT interval prolongation Details Flecainide Trifluoperazine An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Trimethoprim Primsol An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Trimipramine An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Flecainide Triptorelin Increased risk of QT interval prolongation Details Flecainide Vandetanib Caprelsa An increased risk of QT interval prolongation and Torsades de pointes Details Flecainide Vardenafil Levitra An increased risk of QT interval prolongation Details Flecainide Vemurafenib Zelboraf Increased risk of QT interval prolongation Details Flecainide Venlafaxine Increased CYP2D6 substrate exposure and an increased risk of QT interval prolongation Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.