Drug interactions
Piperacillin-tazobactam + Warfarin
Severity: Moderate
Piperacillin-tazobactam 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
Extended-spectrum penicillins can impair platelet function and may alter gut flora, and acute illness itself affects anticoagulation. Together with warfarin this can increase INR or bleeding risk.
What this interaction means in plain words
Piperacillin-tazobactam 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.
Piperacillin-tazobactam belongs to Anti Bacterial; Warfarin belongs to Cardiovascular.
Why it happens
Penicillin-induced platelet dysfunction adds to warfarin anticoagulation, and altered vitamin K-producing gut flora may also contribute.
What to do
Monitor INR more frequently during and after the antibiotic course, and reduce the warfarin dose if needed. Watch for signs of 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 Piperacillin-tazobactam
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 Piperacillin-tazobactam with Warfarin?
MediHelp rates the interaction as moderate. Piperacillin-tazobactam 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. Extended-spectrum penicillins can impair platelet function and may alter gut flora, and acute illness itself affects anticoagulation. Together with warfarin this can increase INR or bleeding risk.
How serious is the interaction between Piperacillin-tazobactam 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: Monitor INR more frequently during and after the antibiotic course, and reduce the warfarin dose if needed. Watch for signs of bleeding.
What other medicines interact with Piperacillin-tazobactam?
MediHelp also lists interactions of Piperacillin-tazobactam with, for example, Vancomycin, Amikacin, Antithrombin alfa. The full list is on the Piperacillin-tazobactam page.
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