What the FDA labels say about taking them together
Disopyramide and ketoconazole
Disopyramide's FDA label of August 24, 2026 names ketoconazole in its drug interactions section; the ketoconazole label PlainMeds reads does not name disopyramide.
Check it at the source: the disopyramide FDA label on DailyMed (effective August 24, 2026, Pfizer Laboratories Div Pfizer Inc); the ketoconazole FDA label on DailyMed (effective January 28, 2026, E. Fougera & Co. a division of Fougera Pharmaceuticals, LLC).
What does the disopyramide label say about ketoconazole?
Disopyramide label, drug interactionsAlthough potent inhibitors of cytochrome P450 3A4 (e.g., ketoconazole) have not been studied clinically, in vitro studies have shown that erythromycin and oleandomycin inhibit the metabolism of disopyramide.
Source: FDA drug label (Norpace), Pfizer Laboratories Div Pfizer Inc, effective August 24, 2026 (SPL set e2aa1642-d262-4520-bc6a-9fd3ad795677), via openFDA; the full label on DailyMed
What does the ketoconazole label say about disopyramide?
Ketoconazole's label (effective January 28, 2026) does not name disopyramide 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
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
| Disopyramide | Ketoconazole | |
|---|---|---|
| Labeled for | n/a | Fungal infections |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.801 per capsule 100 mg capsule | $0.249 per gram 2% cream |
| Shortage now | A presentation being discontinued | 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