What the FDA labels say about taking them together
Macimorelin and quinidine
Macimorelin's FDA label of February 18, 2026 names quinidine in its drug interactions section; the quinidine label PlainMeds reads does not name macimorelin. The macimorelin label: “DRUG INTERACTIONS 7.1 Drugs that Prolong QT Interval Co-administration of MACRILEN with drugs that prolong the QT interval may lead to development of torsade de pointes-type ventricular tachycardia.”
Check it at the source: the macimorelin FDA label on DailyMed (effective February 18, 2026, Aeterna Zentaris GmbH); the quinidine FDA label on DailyMed (effective February 1, 2018, Sun Pharmaceutical Industries, Inc.).
What does the macimorelin label say about quinidine?
Macimorelin label, drug interactionsDRUG INTERACTIONS 7.1 Drugs that Prolong QT Interval Co-administration of MACRILEN with drugs that prolong the QT interval (such as antipsychotic medications (e.g., chlorpromazine, haloperidol, thioridazine, ziprasidone), antibiotics (e.g., moxifloxacin), Class 1A (e.g., quinidine, procainamide) and Class III (e.g., amiodarone, sotalol) antiarrhythmic medications or any other medications known to prolong the QT interval) may lead to development of torsade de pointes-type ventricular tachycardia.
Source: FDA drug label (Macrilen), Aeterna Zentaris GmbH, effective February 18, 2026 (SPL set aeb30f1a-4815-47ae-a2cb-b6b4e26372e1), via openFDA; the full label on DailyMed
What does the quinidine label say about macimorelin?
Quinidine's label (effective February 1, 2018) does not name macimorelin 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
| Macimorelin | Quinidine | |
|---|---|---|
| Labeled for | n/a | Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $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