What the FDA labels say about taking them together
Fosamprenavir and propafenone
Fosamprenavir's FDA label of September 15, 2023 names propafenone in its contraindications section; the propafenone label PlainMeds reads does not name fosamprenavir. The fosamprenavir label: “Coadministration is contraindicated due to potential for serious and/or life-threatening reactions such as cardiac arrhythmias if fosamprenavir is co-prescribed with ritonavir.”
Check it at the source: the fosamprenavir FDA label on DailyMed (effective September 15, 2023, Mylan Pharmaceuticals Inc.); the propafenone FDA label on DailyMed (effective September 1, 2025, Strides Pharma Science Limited).
What does the fosamprenavir label say about propafenone?
Fosamprenavir label, contraindicationsAlfuzosin o Antiarrhythmics: Flecainide (with ritonavir ), propafenone (with ritonavir ) o Antimycobacterial:
Fosamprenavir label, drug interactionsConcomitant Drug Class/Drug Name: Antiarrhythmics: Flecainide, propafenone; Effect on Concentration of Amprenavir or Concomitant Drug: ↑ Antiarrhythmics; Clinical Comment: Coadministration is contraindicated due to potential for serious and/or life-threatening reactions such as cardiac arrhythmias if fosamprenavir is co-prescribed with ritonavir [see ].
Source: FDA drug label (Fosamprenavir Calcium), Mylan Pharmaceuticals Inc., effective September 15, 2023 (SPL set 3a1424d8-844c-4e24-9ebd-b2c2b61b61a3), via openFDA; the full label on DailyMed
What does the propafenone label say about fosamprenavir?
Propafenone's label (effective September 1, 2025) does not name fosamprenavir 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
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
| Fosamprenavir | Propafenone | |
|---|---|---|
| Labeled for | HIV | Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $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