Drug interactions
Cefaclor + Warfarin
Severity: Moderate
Cefaclor 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
Cefaclor has been associated with raised INR and bleeding in patients taking warfarin, based mostly on case reports. The magnitude varies between patients, and acute infection may contribute.
What this interaction means in plain words
Cefaclor 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.
Cefaclor belongs to Anti Bacterial; Warfarin belongs to Cardiovascular.
Why it happens
Not firmly established; possibly reduced gut-derived vitamin K or other effects on warfarin response.
What to do
Check INR within a few days of starting cefaclor and again after stopping it. Adjust the warfarin dose according to INR 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 Cefaclor
- Bcg vaccine live + Cefaclor Moderate
- Cefaclor + Cholera vaccine Moderate
- Cefaclor + Kanamycin Moderate
- Cefaclor + Microbiota Moderate
- Cefaclor + Plazomicin Moderate
- Cefaclor + Sodium picosulfate / magnesium oxide / anhydrous citric acid 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 Cefaclor with Warfarin?
MediHelp rates the interaction as moderate. Cefaclor 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. Cefaclor has been associated with raised INR and bleeding in patients taking warfarin, based mostly on case reports. The magnitude varies between patients, and acute infection may contribute.
How serious is the interaction between Cefaclor 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 cefaclor and again after stopping it. Adjust the warfarin dose according to INR and watch for bleeding.
What other medicines interact with Cefaclor?
MediHelp also lists interactions of Cefaclor with, for example, Bcg vaccine live, Cholera vaccine, Kanamycin. The full list is on the Cefaclor page.
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