Drug interactions
Cefotaxime + Warfarin
Severity: Moderate
Cefotaxime and Warfarin: 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
Cephalosporins can increase the anticoagulant effect of warfarin and raise INR in some patients, increasing the risk of bleeding. Infection itself, reduced food intake and antibiotic effects on gut flora also contribute to this change.
What this interaction means in plain words
Cefotaxime and Warfarin 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.
Cefotaxime belongs to Anti Bacterial; Warfarin belongs to Cardiovascular.
Why it happens
Probably reduced vitamin K availability from gut flora suppression, with the contribution of the acute illness; direct effect on warfarin metabolism is not established.
What to do
Check INR within a few days of starting cefotaxime and again during and after the course. Reduce the warfarin dose if INR rises and watch for bleeding.
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 Cefotaxime
- Cefotaxime + Typhoid vaccine live Major
- Amikacin + Cefotaxime Moderate
- Cefotaxime + Cholera vaccine Moderate
- Cefotaxime + Dexamethasone-tobramycin Moderate
- Cefotaxime + Gentamicin Moderate
- Cefotaxime + Kanamycin Moderate
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 Cefotaxime with Warfarin?
MediHelp rates the interaction as moderate. Cefotaxime and Warfarin 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. Cephalosporins can increase the anticoagulant effect of warfarin and raise INR in some patients, increasing the risk of bleeding. Infection itself, reduced food intake and antibiotic effects on gut flora also contribute to this change.
How serious is the interaction between Cefotaxime and Warfarin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check INR within a few days of starting cefotaxime and again during and after the course. Reduce the warfarin dose if INR rises and watch for bleeding.
What other medicines interact with Cefotaxime?
MediHelp also lists interactions of Cefotaxime with, for example, Typhoid vaccine live, Amikacin, Cholera vaccine. The full list is on the Cefotaxime page.
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