Drug interactions
Dexamethasone + Phenindione
Severity: Moderate
Dexamethasone and Phenindione: moderate 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
Corticosteroids can unpredictably alter the response to oral anticoagulants, either reducing effect or increasing bleeding risk. High-dose steroids also raise gastrointestinal bleeding risk.
What this interaction means in plain words
Dexamethasone and Phenindione can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Mechanism is not firmly established; likely a mix of effects on coagulation factors, vascular integrity and gastric mucosa.
What to do
Monitor INR more frequently when starting, changing or stopping dexamethasone, and adjust the anticoagulant dose accordingly.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Dexamethasone
- Bcg vaccine live + Dexamethasone Contraindicated
- Dexamethasone + Mifepristone Contraindicated
- Dexamethasone + Rilpivirine Contraindicated
- Dexamethasone + Smallpox vaccine live Contraindicated
- Dexamethasone + Varicella virus vaccine live Contraindicated
- Dexamethasone + Yellow fever vaccine Contraindicated
Frequently asked questions
Can I take Dexamethasone with Phenindione?
MediHelp rates the interaction as moderate. Dexamethasone and Phenindione can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Corticosteroids can unpredictably alter the response to oral anticoagulants, either reducing effect or increasing bleeding risk. High-dose steroids also raise gastrointestinal bleeding risk.
How serious is the interaction between Dexamethasone and Phenindione?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor INR more frequently when starting, changing or stopping dexamethasone, and adjust the anticoagulant dose accordingly.
What other medicines interact with Dexamethasone?
MediHelp also lists interactions of Dexamethasone with, for example, Bcg vaccine live, Mifepristone, Rilpivirine. The full list is on the Dexamethasone page.
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