Drug interactions
Fluvoxamine + Warfarin
Severity: Major
Fluvoxamine and Warfarin: major interaction.
Last updated Sources: US FDA label
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
Fluvoxamine can substantially increase warfarin effect and bleeding risk. INR may rise significantly after fluvoxamine is started.
What this interaction means in plain words
Fluvoxamine 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.
Fluvoxamine belongs to Central Nervous System; Warfarin belongs to Cardiovascular.
Why it happens
Fluvoxamine inhibits CYP2C9, CYP1A2 and CYP2C19, reducing warfarin clearance, and SSRI-induced platelet dysfunction adds to bleeding risk.
What to do
Check INR within a few days of starting or stopping fluvoxamine and reduce the warfarin dose as indicated. Consider an alternative antidepressant with less CYP inhibition.
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 Fluvoxamine 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.
References
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 Fluvoxamine
- Agomelatine + Fluvoxamine Contraindicated
- Alosetron + Fluvoxamine Contraindicated
- Fezolinetant + Fluvoxamine Contraindicated
- Fluvoxamine + Isocarboxazid Contraindicated
- Fluvoxamine + Mavacamten Contraindicated
- Fluvoxamine + Methylene blue Contraindicated
Frequently asked questions
Can I take Fluvoxamine with Warfarin?
MediHelp rates the interaction as major. Fluvoxamine 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. Fluvoxamine can substantially increase warfarin effect and bleeding risk. INR may rise significantly after fluvoxamine is started.
How serious is the interaction between Fluvoxamine 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: Check INR within a few days of starting or stopping fluvoxamine and reduce the warfarin dose as indicated. Consider an alternative antidepressant with less CYP inhibition.
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.
