What the FDA labels say about taking them together
Atomoxetine and quinidine
Atomoxetine's FDA label of May 25, 2026 names quinidine in its drug interactions section; the quinidine label PlainMeds reads does not name atomoxetine. The atomoxetine label: “Dosage adjustment of atomoxetine may be necessary when coadministered with potent CYP2D6 inhibitors or when administered to CYP2D6 PMs..”
Check it at the source: the atomoxetine FDA label on DailyMed (effective May 25, 2026, Camber Pharmaceuticals, Inc.); the quinidine FDA label on DailyMed (effective February 1, 2018, Sun Pharmaceutical Industries, Inc.).
What does the atomoxetine label say about quinidine?
Atomoxetine label, drug interactionsInhibitors on Atomoxetine In extensive metabolizers (EMs), inhibitors of CYP2D6 (e.g., paroxetine, fluoxetine, and quinidine) increase atomoxetine steady-state plasma concentrations to exposures similar to those observed in poor metabolizers (PMs).
Atomoxetine label, warnings and precautionsDosage adjustment of atomoxetine may be necessary when coadministered with potent CYP2D6 inhibitors (e.g., paroxetine, fluoxetine, and quinidine) or when administered to CYP2D6 PMs. [see Dosage and Administration ( 2.5 ) and Drug Interactions ( 7.2 )].
Source: FDA drug label (Atomoxetine), ANDA202682 (Hetero Labs Ltd V), as published by Camber Pharmaceuticals, Inc., effective May 25, 2026 (SPL set f266ab7b-5a68-42b5-b204-e3249bea0aed), via openFDA; the full label on DailyMed
What does the quinidine label say about atomoxetine?
Quinidine's label (effective February 1, 2018) does not name atomoxetine 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
| Atomoxetine | Quinidine | |
|---|---|---|
| Labeled for | ADHD | Atrial fibrillation |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.442 per capsule 40 mg capsule | $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