Drug interactions
Ketoconazole + Mestranol
Severity: Moderate
Ketoconazole and Mestranol: 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 may increase estrogen exposure from mestranol, which may heighten estrogenic adverse effects such as breakthrough bleeding, nausea and thromboembolic risk.
What this interaction means in plain words
Ketoconazole and Mestranol 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.
Why it happens
CYP3A4 inhibition by ketoconazole reduces estrogen metabolism.
What to do
Monitor for estrogenic adverse effects and consider an alternative antifungal or lower-estrogen contraception for prolonged therapy.
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?
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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
Frequently asked questions
Can I take Ketoconazole with Mestranol?
MediHelp rates the interaction as moderate. Ketoconazole and Mestranol 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 may increase estrogen exposure from mestranol, which may heighten estrogenic adverse effects such as breakthrough bleeding, nausea and thromboembolic risk.
How serious is the interaction between Ketoconazole and Mestranol?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for estrogenic adverse effects and consider an alternative antifungal or lower-estrogen contraception for prolonged therapy.
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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