What the FDA labels say about taking them together
Ketoconazole and tofacitinib
Tofacitinib's FDA label of July 13, 2026 names ketoconazole in its drug interactions section; the ketoconazole label PlainMeds reads does not name tofacitinib. The tofacitinib label: “Clinically Significant Interactions Affecting XELJANZ/XELJANZ XR When Concomitantly Used with Other Drugs Strong CYP3A4 Inhibitors (e.g., ketoconazole) Clinical Impact Increased exposure to tofacitinib Intervention …”
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 tofacitinib FDA label on DailyMed (effective July 13, 2026, U.S. Pharmaceuticals).
What does the ketoconazole label say about tofacitinib?
Ketoconazole's label (effective January 28, 2026) does not name tofacitinib 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 tofacitinib label say about ketoconazole?
Tofacitinib label, drug interactionsClinically Significant Interactions Affecting XELJANZ/XELJANZ XR When Concomitantly Used with Other Drugs Strong CYP3A4 Inhibitors (e.g., ketoconazole) Clinical Impact Increased exposure to tofacitinib Intervention Dosage modification of XELJANZ/XELJANZ XR is recommended [see Dosage and Administration (2), Clinical Pharmacology, Figure 3 (12.3) ] Moderate CYP3A4 Inhibitors Concomitantly Used with Strong CYP2C19 Inhibitors (e.g., fluconazole) Clinical Impact Increased exposure to tofacitinib Intervention Dosage modification of XELJANZ/XELJANZ XR is recommended [see Dosage and Administration (2), Clinical Pharmacology, Figure 3 (12.3) ] Strong CYP3A4 Inducers (e.g., rifampin) Clinical Impact …
Source: FDA drug label (XELJANZ), NDA203214 (Pf Prism Cv), as published by U.S. Pharmaceuticals, effective July 13, 2026 (SPL set 68e3d6b2-7838-4d2d-a417-09d919b43e13), 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 | Tofacitinib | |
|---|---|---|
| Labeled for | Fungal infections | Rheumatoid arthritis, Crohn's disease and ulcerative colitis |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.249 per gram 2% cream | $0.573 per tablet 5 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