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What the FDA labels say about taking them together

Propafenone and terbinafine

Terbinafine's FDA label of October 17, 2025 names propafenone in its drug interactions section; the propafenone label PlainMeds reads does not name terbinafine. The terbinafine label: “Drugs predominantly metabolized by the CYP450 2D6 isozyme include the following drug classes: tricyclic antidepressants, selective serotonin reuptake inhibitors, beta-blockers, antiarrhythmics class 1C and monoamine …”

Check it at the source: the propafenone FDA label on DailyMed (effective September 1, 2025, Strides Pharma Science Limited); the terbinafine FDA label on DailyMed (effective October 17, 2025, PD-Rx Pharmaceuticals, Inc.).

What does the propafenone label say about terbinafine?

Propafenone's label (effective September 1, 2025) does not name terbinafine in these sections. A label lists what its studies and reports found; it is not a complete list.

Source: FDA drug label (PROPAFENONE HYDROCHLORIDE), Strides Pharma Science Limited, effective September 1, 2025 (SPL set c65253ab-937f-4982-b841-69c2b9f9ccdb), via openFDA; the full label on DailyMed

What does the terbinafine label say about propafenone?

Terbinafine label, drug interactions

Drugs predominantly metabolized by the CYP450 2D6 isozyme include the following drug classes: tricyclic antidepressants, selective serotonin reuptake inhibitors, beta-blockers, antiarrhythmics class 1C (e.g., flecainide and propafenone) and monoamine oxidase inhibitors Type B. Coadministration of Terbinafine tablets should be done with careful monitoring and may require a reduction in dose of the 2D6-metabolized drug.

Source: FDA drug label (Terbinafine Hydrochloride), PD-Rx Pharmaceuticals, Inc., effective October 17, 2025 (SPL set 2df111dc-ecac-4161-9e22-38436eb37c1f), via openFDA; the full label on DailyMed

These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.

Both medicines on the record

14Propafenone generic labelers
39Terbinafine generic labelers
PropafenoneTerbinafine
Labeled forAtrial fibrillationFungal infections
Boxed warningYesNo
Pharmacy cost (NADAC)$0.115 per tablet 150 mg tablet$0.143 per tablet 250 mg tablet
Shortage nowNo current entryNo current entry

Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)

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