What the FDA labels say about taking them together
Carvedilol and quinidine
Carvedilol's FDA label of July 31, 2026 names quinidine in its drug interactions section; the quinidine label PlainMeds reads does not name carvedilol. The carvedilol label: “Inhibitors and Poor Metabolizers Interactions of carvedilol with potent inhibitors of CYP2D6 isoenzyme have not been studied, but these drugs would be expected to increase blood levels of the R(+) enantiomer of …”
Check it at the source: the carvedilol FDA label on DailyMed (effective July 31, 2026, Waylis Therapeutics LLC); the quinidine FDA label on DailyMed (effective February 1, 2018, Sun Pharmaceutical Industries, Inc.).
What does the carvedilol label say about quinidine?
Carvedilol label, drug interactionsInhibitors and Poor Metabolizers Interactions of carvedilol with potent inhibitors of CYP2D6 isoenzyme (such as quinidine, fluoxetine, paroxetine, and propafenone) have not been studied, but these drugs would be expected to increase blood levels of the R(+) enantiomer of carvedilol [see Clinical Pharmacology (12.3) ].
Source: FDA drug label (Coreg), Waylis Therapeutics LLC, effective July 31, 2026 (SPL set 07c619c6-4a0c-445e-94fa-664a54f68a39), via openFDA; the full label on DailyMed
What does the quinidine label say about carvedilol?
Quinidine's label (effective February 1, 2018) does not name carvedilol 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
| Carvedilol | Quinidine | |
|---|---|---|
| Labeled for | Heart failure, High blood pressure | Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0179 per tablet 6.25 mg tablet | $4.92 per tablet 324 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