Drug interactions
Cobicistat + Ketoconazole
Severity: Moderate
Cobicistat and Ketoconazole: moderate 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 and cobicistat both inhibit CYP3A4 and may raise each other's concentrations. This may increase ketoconazole-related adverse effects and exposure to other co-administered CYP3A substrates.
What this interaction means in plain words
Cobicistat and Ketoconazole can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Cobicistat belongs to Miscellaneous; Ketoconazole belongs to Anti Fungals.
Why it happens
Mutual CYP3A4 inhibition, with cobicistat being a CYP3A substrate.
What to do
Limit ketoconazole dose, commonly to 200 mg daily with cobicistat-containing regimens, and monitor for hepatotoxicity and QT effects.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Cobicistat and Ketoconazole, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Other interactions of Cobicistat
- Alfuzosin + Cobicistat Contraindicated
- Apalutamide + Cobicistat Contraindicated
- Cobicistat + Colchicine Contraindicated
- Cobicistat + Dronedarone Contraindicated
- Cobicistat + Eletriptan Contraindicated
- Cobicistat + Eplerenone Contraindicated
Frequently asked questions
Can I take Cobicistat with Ketoconazole?
MediHelp rates the interaction as moderate. Cobicistat and Ketoconazole can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Ketoconazole and cobicistat both inhibit CYP3A4 and may raise each other's concentrations. This may increase ketoconazole-related adverse effects and exposure to other co-administered CYP3A substrates.
How serious is the interaction between Cobicistat and Ketoconazole?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Limit ketoconazole dose, commonly to 200 mg daily with cobicistat-containing regimens, and monitor for hepatotoxicity and QT effects.
What other medicines interact with Ketoconazole?
MediHelp also lists interactions of Ketoconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Ketoconazole page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
