Erythromycin and Warfarin: Drug Interaction Guide
Quick answer: This combination requires caution. Erythromycin and Warfarin can be used together with adjustments and monitoring.
How Erythromycin interacts with Warfarin
Erythromycin inhibits CYP3A4 and CYP1A2 metabolism of warfarin and disrupts gut flora producing vitamin K, potentiating anticoagulant effect.
What you should do
Monitor INR within 3-5 days of starting erythromycin and adjust warfarin dose accordingly. Consider azithromycin if antibiotic still required.
Key facts
Severity
Moderate — caution required
Mechanism
Erythromycin inhibits CYP3A4 and CYP1A2 metabolism of warfarin and disrupts gut flora producing vitamin K, potentiating ...
Action
Monitor INR within 3-5 days of starting erythromycin and adjust warfarin dose accordingly. Consider azithromycin if anti...
Frequently asked questions
Can I take Erythromycin and Warfarin together?
With caution. Monitor INR within 3-5 days of starting erythromycin and adjust warfarin dose accordingly. Consider azithromycin if antibiotic still required.
What is the severity of this interaction?
The interaction between Erythromycin and Warfarin is classified as Moderate — caution required. Erythromycin inhibits CYP3A4 and CYP1A2 metabolism of warfarin and disrupts gut flora producing vitamin K, potentiating anticoagulant effect.
What should I do if I'm prescribed both?
Monitor INR within 3-5 days of starting erythromycin and adjust warfarin dose accordingly. Consider azithromycin if antibiotic still required. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.