Drug interactions
Simvastatin + Warfarin
Severity: Minor
Simvastatin and Warfarin: minor 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
Simvastatin may slightly increase the INR in patients on warfarin, though changes are usually small. Bleeding is uncommon but possible.
What this interaction means in plain words
Simvastatin and Warfarin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Simvastatin belongs to Cardiovascular; Warfarin belongs to Cardiovascular.
Why it happens
Mechanism uncertain; possibly minor competition for CYP-mediated metabolism.
What to do
Check INR after starting or changing the simvastatin dose and adjust warfarin if needed.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Other interactions of Simvastatin
- Atazanavir + Simvastatin Contraindicated
- Clarithromycin + Simvastatin Contraindicated
- Cobicistat + Simvastatin Contraindicated
- Cyclosporine + Simvastatin Contraindicated
- Cyclosporin + Simvastatin Contraindicated
- Danazol + Simvastatin Contraindicated
Frequently asked questions
Can I take Simvastatin with Warfarin?
MediHelp rates the interaction as minor. Simvastatin and Warfarin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Simvastatin may slightly increase the INR in patients on warfarin, though changes are usually small. Bleeding is uncommon but possible.
How serious is the interaction between Simvastatin and Warfarin?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check INR after starting or changing the simvastatin dose and adjust warfarin if needed.
What other medicines interact with Warfarin?
MediHelp also lists interactions of Warfarin with, for example, Defibrotide, Ketorolac, Abciximab. The full list is on the Warfarin page.
Full monographs, dosing and an interaction checker in the MediHelp app
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