Flecainide and Propranolol interaction
Flecainide and Propranolol: the Flecainide prescribing label 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 Flecainide (Flecainide Acetate) label · effective 2026-02-06
Concomitant negative chronotropic therapy such as digoxin or beta-blockers may lower the risk of this complication.
In a study involving healthy subjects receiving flecainide acetate and propranolol concurrently, plasma flecainide levels were increased about 20% and propranolol levels were increased about 30% compared to control values.
In this formal interaction study, flecainide acetate and propranolol were each found to have negative inotropic effects; when the drugs were administered together, the effects were additive.
The effects of concomitant administration of flecainide acetate and propranolol on the PR interval were less than additive.
In flecainide acetate clinical trials, patients who were receiving beta blockers concurrently did not experience an increased incidence of side effects.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.