What the FDA labels say about taking them together
Flecainide and propafenone
Propafenone's FDA label of September 1, 2025 names flecainide in its boxed warning section; the flecainide label PlainMeds reads does not name propafenone. The propafenone label: “An increased rate of death or reversed cardiac arrest rate was seen in subjects treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in subjects assigned to placebo.”
Check it at the source: the flecainide FDA label on DailyMed (effective June 11, 2026, Amneal Pharmaceuticals of New York LLC); the propafenone FDA label on DailyMed (effective September 1, 2025, Strides Pharma Science Limited).
What does the flecainide label say about propafenone?
Flecainide's label (effective June 11, 2026) does not name propafenone in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Flecainide Acetate), Amneal Pharmaceuticals of New York LLC, effective June 11, 2026 (SPL set ee9595d5-08a1-4529-9215-ddc3c7f929c4), via openFDA; the full label on DailyMed
What does the propafenone label say about flecainide?
Propafenone label, boxed warningAn increased rate of death or reversed cardiac arrest rate was seen in subjects treated with encainide or flecainide (Class IC antiarrhythmics) compared with that seen in subjects assigned to placebo.
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
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
| Flecainide | Propafenone | |
|---|---|---|
| Labeled for | n/a | Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.171 per tablet 100 mg tablet | $0.115 per tablet 150 mg tablet |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once