What the FDA labels say about taking them together
Milsaperidone and quinidine
Milsaperidone's FDA label of February 27, 2026 names quinidine in its warnings and precautions section; the quinidine label PlainMeds reads does not name milsaperidone.
Check it at the source: the milsaperidone FDA label on DailyMed (effective February 27, 2026, Vanda Pharmaceuticals Inc.); the quinidine FDA label on DailyMed (effective February 1, 2018, Sun Pharmaceutical Industries, Inc.).
What does the milsaperidone label say about quinidine?
Milsaperidone label, warnings and precautionsSteps to Prevent or Mitigate Clinically Significant Adverse Reactions or Risks Associated with QTc Interval Prolongation The concomitant use of BYSANTI should be avoided with other drugs that prolong the QTc interval including Class 1A antiarrhythmics (e.g., quinidine, procainamide) or Class III antiarrhythmics (e.g., amiodarone, sotalol), antipsychotic drugs that prolong the QTc interval (e.g., chlorpromazine, thioridazine), antibiotics that prolong the QTc interval (e.g., gatifloxacin, moxifloxacin), or any other class of drugs known to prolong the QTc interval (e.g., pentamidine, levomethadyl acetate, methadone).
Source: FDA drug label (BYSANTI), Vanda Pharmaceuticals Inc., effective February 27, 2026 (SPL set 254a1c01-4a4c-4bdd-85d6-1f23f2e4e6f8), via openFDA; the full label on DailyMed
What does the quinidine label say about milsaperidone?
Quinidine's label (effective February 1, 2018) does not name milsaperidone 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
| Milsaperidone | Quinidine | |
|---|---|---|
| Labeled for | Schizophrenia, Bipolar disorder | Atrial fibrillation |
| Boxed warning | Yes | 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