What the FDA labels say about taking them together
Cobicistat and quinidine
Cobicistat's FDA label of February 10, 2026 names quinidine in its drug interactions section; the quinidine label PlainMeds reads does not name cobicistat. The cobicistat label: “Clinical monitoring is recommended upon coadministration with antiarrhythmics.”
Check it at the source: the cobicistat FDA label on DailyMed (effective February 10, 2026, Gilead Sciences, Inc.); the quinidine FDA label on DailyMed (effective February 1, 2018, Sun Pharmaceutical Industries, Inc.).
What does the cobicistat label say about quinidine?
Cobicistat label, drug interactionsConcomitant Drug Class/Drug Name: Other antiarrhythmics: e.g., amiodarone disopyramide flecainide mexiletine propafenone quinidine; Potential Effect ↑ = Increase, ↓ = Decrease, ↔ = No change: ↑ antiarrhythmics; Clinical Comment: Clinical monitoring is recommended upon coadministration with antiarrhythmics.
Source: FDA drug label (Tybost), Gilead Sciences, Inc., effective February 10, 2026 (SPL set 3784c35c-e87f-410c-900b-8fd6313c6010), via openFDA; the full label on DailyMed
What does the quinidine label say about cobicistat?
Quinidine's label (effective February 1, 2018) does not name cobicistat in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Quinidine Gluconate), Sun Pharmaceutical Industries, Inc., effective February 1, 2018 (SPL set 5023f053-fcc4-4c2c-aa59-9ec198ad185e), 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
| Cobicistat | Quinidine | |
|---|---|---|
| Labeled for | HIV | Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $4.92 per tablet 324 mg tablet |
| Shortage now | A presentation being discontinued | 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