Drug interactions
Phenindione + Piroxicam
Severity: Major
Phenindione and Piroxicam: 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
Phenindione is a vitamin K antagonist, and piroxicam adds platelet inhibition and gastric mucosal injury. The combination markedly increases the risk of gastrointestinal and other hemorrhage.
What this interaction means in plain words
Phenindione and Piroxicam 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: vitamin K antagonism plus NSAID platelet inhibition, with possible protein-binding displacement.
What to do
Avoid concurrent use and choose a non-NSAID analgesic. If unavoidable, monitor INR closely, watch for bleeding 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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Other interactions of Piroxicam
- Ketorolac intranasal + Piroxicam Contraindicated
- Ketorolac + Piroxicam Contraindicated
- Aceclofenac + Piroxicam Major
- Acemetacin + Piroxicam Major
- Acetylsalicylic acid + Piroxicam Major
- Alteplase + Piroxicam Major
Frequently asked questions
Can I take Phenindione with Piroxicam?
MediHelp rates the interaction as major. Phenindione and Piroxicam 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. Phenindione is a vitamin K antagonist, and piroxicam adds platelet inhibition and gastric mucosal injury. The combination markedly increases the risk of gastrointestinal and other hemorrhage.
How serious is the interaction between Phenindione and Piroxicam?
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 concurrent use and choose a non-NSAID analgesic. If unavoidable, monitor INR closely, watch for bleeding and consider gastroprotection.
What other medicines interact with Piroxicam?
MediHelp also lists interactions of Piroxicam with, for example, Ketorolac intranasal, Ketorolac, Aceclofenac. The full list is on the Piroxicam page.
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