Dronedarone and Duloxetine interaction
Dronedarone and Duloxetine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Dronedarone (Multaq) label · effective 2026-01-27
…(12.3) ] • Concomitant use of drugs or herbal products that prolong the QT interval and might increase the risk of torsade de pointes, such as phenothiazine antipsychotics, tricyclic antidepressants, certain oral macrolide antibiotics, and Class I and III antiarrhythmics • Liver or lung toxicity related to the previous use of amiodarone • QTc interval >500 ms or…
Pharmacodynamic Interactions Drugs Prolonging the QT Interval (Inducing Torsade de Pointes) Coadministration of drugs prolonging the QT interval (such as certain phenothiazines, tricyclic antidepressants, certain macrolide antibiotics, and Class I and III antiarrhythmics) is contraindicated because of the potential risk of torsade de pointes–type ventricular tachycardia…
Other CYP2D6 substrates, including other beta-blockers, tricyclic antidepressants, and selective serotonin reuptake inhibitors (SSRIs) may have increased exposure upon coadministration with dronedarone [see Drug Interactions (7.1) , Clinical Pharmacology (12.3) ] .
From the Duloxetine (Cymbalta) label · effective 2025-07-21
…Co-administration of CYMBALTA with drugs that are extensively metabolized by CYP2D6 and that have a narrow therapeutic index, including certain antidepressants (tricyclic antidepressants [TCAs], such as nortriptyline, amitriptyline, and imipramine), phenothiazines and Type 1C antiarrhythmics (e.g., propafenone, flecainide), should be approached with caution.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.