Drug interactions
Ketoconazole + Tofacitinib
Severity: Major
Ketoconazole and Tofacitinib: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Ketoconazole is a potent CYP3A4 inhibitor and increases tofacitinib systemic exposure. This raises the risk of dose-related adverse effects such as infection and cytopenias.
What this interaction means in plain words
Ketoconazole and Tofacitinib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Ketoconazole belongs to Anti Fungals; Tofacitinib belongs to Musculoskeletal.
Why it happens
Potent CYP3A4 inhibition reduces tofacitinib clearance.
What to do
Reduce tofacitinib dose per labeling, for example to 5 mg once daily when the usual dose is 5 mg twice daily. Monitor for infection and blood counts.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Tofacitinib
- Baricitinib + Tofacitinib Contraindicated
- Cladribine + Tofacitinib Contraindicated
- Tofacitinib + Upadacitinib Contraindicated
- Abatacept + Tofacitinib Major
- Anti-thymocyte + Tofacitinib Major
- Antithymocyte globulin equine + Tofacitinib Major
Other interactions of Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Frequently asked questions
Can I take Ketoconazole with Tofacitinib?
MediHelp rates the interaction as major. Ketoconazole and Tofacitinib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Ketoconazole is a potent CYP3A4 inhibitor and increases tofacitinib systemic exposure. This raises the risk of dose-related adverse effects such as infection and cytopenias.
How serious is the interaction between Ketoconazole and Tofacitinib?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reduce tofacitinib dose per labeling, for example to 5 mg once daily when the usual dose is 5 mg twice daily. Monitor for infection and blood counts.
What other medicines interact with Tofacitinib?
MediHelp also lists interactions of Tofacitinib with, for example, Baricitinib, Cladribine, Upadacitinib. The full list is on the Tofacitinib page.
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