Drug interactions
Cefdinir + Warfarin
Severity: Moderate
Cefdinir 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 occasionally raise INR in patients on warfarin, increasing bleeding risk. The effect is variable and is often confounded by the underlying infection and reduced intake.
What this interaction means in plain words
Cefdinir 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.
Cefdinir belongs to Anti Bacterial; Warfarin belongs to Cardiovascular.
Why it happens
Possible reduction in vitamin K-producing gut flora and reduced vitamin K availability; mechanism not firmly established.
What to do
Check INR within a few days of starting cefdinir and after stopping it, adjusting warfarin dose as needed. Counsel the patient on bleeding signs.
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 Cefdinir
- Aluminum hydroxide + Cefdinir Moderate
- Cefdinir + Cholera vaccine Moderate
- Cefdinir + Famotidine Moderate
- Cefdinir + Gentamicin Moderate
- Cefdinir + Microbiota Moderate
- Cefdinir + Nizatidine 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 Cefdinir with Warfarin?
MediHelp rates the interaction as moderate. Cefdinir 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 occasionally raise INR in patients on warfarin, increasing bleeding risk. The effect is variable and is often confounded by the underlying infection and reduced intake.
How serious is the interaction between Cefdinir 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 cefdinir and after stopping it, adjusting warfarin dose as needed. Counsel the patient on bleeding signs.
What other medicines interact with Cefdinir?
MediHelp also lists interactions of Cefdinir with, for example, Aluminum hydroxide, Cholera vaccine, Famotidine. The full list is on the Cefdinir page.
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