Drug interactions
Diflunisal + Phenindione
Severity: Major
Diflunisal and Phenindione: 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, may cause GI bleeding and may displace oral anticoagulants from protein binding, increasing bleeding risk. Serious hemorrhage may result.
What this interaction means in plain words
Diflunisal 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 hemostatic impairment with antiplatelet effect, mucosal injury and possible protein-binding displacement of the anticoagulant.
What to do
Avoid if possible and choose paracetamol for analgesia. If combined, monitor INR closely and watch for bleeding.
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
Frequently asked questions
Can I take Diflunisal with Phenindione?
MediHelp rates the interaction as major. Diflunisal 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. Diflunisal inhibits platelet function, may cause GI bleeding and may displace oral anticoagulants from protein binding, increasing bleeding risk. Serious hemorrhage may result.
How serious is the interaction between Diflunisal 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 if possible and choose paracetamol for analgesia. If combined, monitor INR closely and watch for bleeding.
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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