Drug interactions
Mifepristone + Phenindione
Severity: Major
Mifepristone and Phenindione: 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
Mifepristone causes uterine bleeding when used to end pregnancy, and phenindione, a vitamin K antagonist, impairs clotting. The combination may lead to excessive or prolonged hemorrhage.
What this interaction means in plain words
Mifepristone and Phenindione 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.
Why it happens
Additive bleeding risk from vitamin K antagonism and mifepristone-induced uterine bleeding.
What to do
Avoid medical abortion with mifepristone in anticoagulated patients; consider surgical management with INR monitoring. If used, check INR and hemoglobin and ensure access to emergency care.
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 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 Mifepristone with Phenindione?
MediHelp rates the interaction as major. Mifepristone and Phenindione 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. Mifepristone causes uterine bleeding when used to end pregnancy, and phenindione, a vitamin K antagonist, impairs clotting. The combination may lead to excessive or prolonged hemorrhage.
How serious is the interaction between Mifepristone and Phenindione?
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 medical abortion with mifepristone in anticoagulated patients; consider surgical management with INR monitoring. If used, check INR and hemoglobin and ensure access to emergency care.
What other medicines interact with Mifepristone?
MediHelp also lists interactions of Mifepristone with, for example, Apixaban, Argatroban, Cisapride. The full list is on the Mifepristone page.
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