Green Tea × Warfarin

Severity: MODERATE Evidence: well-established

Mechanism

Green tea contains vitamin K which can antagonize warfarin. High consumption may reduce INR.

Effect

Reduced anticoagulant effect at high consumption (>1/2 gallon/day)

Management

Maintain consistent green tea intake. Avoid sudden changes in consumption.

Source

Taylor JR, Wilt VM. Pharmacotherapy 1999

⚠️ MODERATE INTERACTION: Monitor closely if this combination is used.

Disclaimer

This interaction record is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider before starting or stopping any supplement or medication.