Drug interactions
Capecitabine + Warfarin
Severity: Major
Capecitabine and Warfarin: 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
Capecitabine can markedly increase INR in patients on warfarin, and bleeding events including fatal haemorrhage have been reported. The effect may appear within days of starting or months later and can persist after stopping capecitabine.
What this interaction means in plain words
Capecitabine and Warfarin 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.
Capecitabine belongs to Oncology; Warfarin belongs to Cardiovascular.
Why it happens
Likely inhibition of CYP2C9-mediated warfarin metabolism by capecitabine or its metabolites.
What to do
Monitor INR and prothrombin time frequently, at least weekly initially, and reduce the warfarin dose as needed. Consider switching to a different anticoagulant such as low-molecular-weight heparin or a direct oral anticoagulant.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Capecitabine and Warfarin, 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 Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Other interactions of Capecitabine
Frequently asked questions
Can I take Capecitabine with Warfarin?
MediHelp rates the interaction as major. Capecitabine and Warfarin 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. Capecitabine can markedly increase INR in patients on warfarin, and bleeding events including fatal haemorrhage have been reported. The effect may appear within days of starting or months later and can persist after stopping capecitabine.
How serious is the interaction between Capecitabine and Warfarin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor INR and prothrombin time frequently, at least weekly initially, and reduce the warfarin dose as needed. Consider switching to a different anticoagulant such as low-molecular-weight heparin or a direct oral anticoagulant.
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
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
