Drug interactions
Ketoconazole + Mifepristone
Severity: Major
Ketoconazole and Mifepristone: 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 raises mifepristone concentrations, which may increase adverse effects including QT prolongation, adrenal insufficiency effects and hypokalemia with the Cushing's syndrome dose.
What this interaction means in plain words
Ketoconazole and Mifepristone 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; Mifepristone belongs to Endocrine.
Why it happens
Strong CYP3A4 inhibition reduces mifepristone metabolism.
What to do
Avoid the combination where possible. With Cushing's dosing, limit the mifepristone dose per labeling and monitor potassium, ECG and signs of adrenal insufficiency.
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 Ketoconazole
- Alfuzosin + Ketoconazole Contraindicated
- Alprazolam + Ketoconazole Contraindicated
- Avanafil + Ketoconazole Contraindicated
- Conivaptan + Ketoconazole Contraindicated
- Dihydroergotamine intranasal + Ketoconazole Contraindicated
- Dihydroergotamine + Ketoconazole Contraindicated
Other interactions of Mifepristone
- Apixaban + Mifepristone Contraindicated
- Argatroban + Mifepristone Contraindicated
- Cisapride + Mifepristone Contraindicated
- Cortisone + Mifepristone Contraindicated
- Cyclosporin + Mifepristone Contraindicated
- Dabigatran etexilate + Mifepristone Contraindicated
Frequently asked questions
Can I take Ketoconazole with Mifepristone?
MediHelp rates the interaction as major. Ketoconazole and Mifepristone 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 raises mifepristone concentrations, which may increase adverse effects including QT prolongation, adrenal insufficiency effects and hypokalemia with the Cushing's syndrome dose.
How serious is the interaction between Ketoconazole and Mifepristone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible. With Cushing's dosing, limit the mifepristone dose per labeling and monitor potassium, ECG and signs of adrenal insufficiency.
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.
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