See also How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Many drugs besides propafenone may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, flecainide, pimozide, procainamide, quinidine, sotalol, macrolide antibiotics (such as erythromycin), and certain quinolone antibiotics (such as sparfloxacin), among others.

Other medications can affect the removal of propafenone from your body, which may affect how propafenone works. Examples include asunaprevir, desipramine, ketoconazole, orlistat, phenobarbital, phenytoin, ritonavir, certain HIV protease inhibitors (such as tipranavir), among others.

Propafenone can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include digoxin, fezolinetant, imipramine, metoprolol, propranolol, warfarin, among others.