Drug interactions
Indomethacin + Phenindione
Severity: Major
Indomethacin and Phenindione: 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 indomethacin adds platelet inhibition and the risk of GI ulceration. Combined use significantly increases the risk of serious bleeding.
What this interaction means in plain words
Indomethacin 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 effects: vitamin K-dependent clotting factor depletion plus NSAID platelet inhibition and mucosal injury.
What to do
Avoid the combination where possible; if unavoidable, monitor INR and signs of bleeding and consider GI protection.
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 Indomethacin and Phenindione, 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 Indomethacin
- Indomethacin + Ketorolac Contraindicated
- Indomethacin + Ketorolac intranasal Contraindicated
- Aceclofenac + Indomethacin Major
- Acemetacin + Indomethacin Major
- Acetylsalicylic acid + Indomethacin Major
- Alteplase + Indomethacin Major
Frequently asked questions
Can I take Indomethacin with Phenindione?
MediHelp rates the interaction as major. Indomethacin 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. Phenindione is a vitamin K antagonist, and indomethacin adds platelet inhibition and the risk of GI ulceration. Combined use significantly increases the risk of serious bleeding.
How serious is the interaction between Indomethacin 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 the combination where possible; if unavoidable, monitor INR and signs of bleeding and consider GI protection.
What other medicines interact with Indomethacin?
MediHelp also lists interactions of Indomethacin with, for example, Ketorolac, Ketorolac intranasal, Aceclofenac. The full list is on the Indomethacin 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.