Drug interactions
Diflunisal + Warfarin
Severity: Major
Diflunisal 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
Diflunisal inhibits platelet function and can injure the gastric mucosa, so combining it with warfarin substantially raises the risk of serious bleeding. Diflunisal may also modestly increase the anticoagulant effect of warfarin.
What this interaction means in plain words
Diflunisal 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.
Diflunisal belongs to Musculoskeletal; Warfarin belongs to Cardiovascular.
Why it happens
Additive impairment of hemostasis from NSAID antiplatelet action and mucosal injury plus warfarin anticoagulation, with possible protein-binding displacement.
What to do
Avoid the combination and use paracetamol or another alternative where possible; if unavoidable, monitor INR closely, use the shortest course and consider gastroprotection.
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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References
Other interactions of Diflunisal
- Diflunisal + Ketorolac Contraindicated
- Diflunisal + Ketorolac intranasal Contraindicated
- Acemetacin + Diflunisal Major
- Acetazolamide + Diflunisal Major
- Alteplase + Diflunisal Major
- Amiloride + Diflunisal Major
Other interactions of Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Frequently asked questions
Can I take Diflunisal with Warfarin?
MediHelp rates the interaction as major. Diflunisal 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. Diflunisal inhibits platelet function and can injure the gastric mucosa, so combining it with warfarin substantially raises the risk of serious bleeding. Diflunisal may also modestly increase the anticoagulant effect of warfarin.
How serious is the interaction between Diflunisal 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: Avoid the combination and use paracetamol or another alternative where possible; if unavoidable, monitor INR closely, use the shortest course and consider gastroprotection.
What other medicines interact with Diflunisal?
MediHelp also lists interactions of Diflunisal with, for example, Ketorolac, Ketorolac intranasal, Acemetacin. The full list is on the Diflunisal page.
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