Drug interactions
Mestranol + Ribociclib
Severity: Moderate
Mestranol and Ribociclib: 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
Mestranol is a prodrug converted to ethinylestradiol, which is partly metabolized by CYP3A4. Ribociclib may increase estrogen exposure, with possible estrogenic adverse effects. Hormonal contraceptives are also generally unsuitable in hormone receptor-positive breast cancer.
What this interaction means in plain words
Mestranol and Ribociclib 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
Inhibition of CYP3A4-mediated estrogen metabolism by ribociclib.
What to do
Reassess the need for estrogen-containing products in breast cancer patients and prefer non-hormonal contraception; if used, monitor for estrogenic adverse effects and blood pressure.
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 Mestranol and Ribociclib, 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 Ribociclib
- Amiodarone + Ribociclib Contraindicated
- Cisapride + Ribociclib Contraindicated
- Dofetilide + Ribociclib Contraindicated
- Dronedarone + Ribociclib Contraindicated
- Flibanserin + Ribociclib Contraindicated
- Ibutilide + Ribociclib Contraindicated
Frequently asked questions
Can I take Mestranol with Ribociclib?
MediHelp rates the interaction as moderate. Mestranol and Ribociclib 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. Mestranol is a prodrug converted to ethinylestradiol, which is partly metabolized by CYP3A4. Ribociclib may increase estrogen exposure, with possible estrogenic adverse effects. Hormonal contraceptives are also generally unsuitable in hormone receptor-positive breast cancer.
How serious is the interaction between Mestranol and Ribociclib?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reassess the need for estrogen-containing products in breast cancer patients and prefer non-hormonal contraception; if used, monitor for estrogenic adverse effects and blood pressure.
What other medicines interact with Ribociclib?
MediHelp also lists interactions of Ribociclib with, for example, Amiodarone, Cisapride, Dofetilide. The full list is on the Ribociclib 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.
