What the FDA labels say about taking them together
Ketoconazole and quetiapine
Quetiapine's FDA label of April 10, 2026 names ketoconazole in its drug interactions section; the ketoconazole label PlainMeds reads does not name quetiapine. The quetiapine label: “Concomitant use of strong CYP3A4 inhibitors: Reduce quetiapine dose to one sixth when coadministered with strong CYP3A4 inhibitors”
Check it at the source: the ketoconazole FDA label on DailyMed (effective January 28, 2026, E. Fougera & Co. a division of Fougera Pharmaceuticals, LLC); the quetiapine FDA label on DailyMed (effective April 10, 2026, H2-Pharma, LLC).
What does the ketoconazole label say about quetiapine?
Ketoconazole's label (effective January 28, 2026) does not name quetiapine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (ketoconazole), E. Fougera & Co. a division of Fougera Pharmaceuticals, LLC, effective January 28, 2026 (SPL set cad7c647-34a9-4e4e-83b3-8d78e58f588f), via openFDA; the full label on DailyMed
What does the quetiapine label say about ketoconazole?
Quetiapine label, drug interactionsConcomitant use of strong CYP3A4 inhibitors: Reduce quetiapine dose to one sixth when coadministered with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir)
Source: FDA drug label (SEROQUEL), NDA020639 (Cheplapharm), as published by H2-Pharma, LLC, effective April 10, 2026 (SPL set 8ae62aaf-f8c5-417f-baac-0098369ca322), 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
| Ketoconazole | Quetiapine | |
|---|---|---|
| Labeled for | Fungal infections | Schizophrenia, Bipolar disorder, Depression |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.249 per gram 2% cream | $0.127 per tablet 300 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