Increasing Vitamin K intake in a patient on warfarin affects INR how?

Increasing Vitamin K intake in a patient on warfarin affects INR how?

• A. No effect
• B. Lower INR
• C. Fluctuating unpredictably
• D. Higher INR

Answer: (B)

Increasing vitamin K intake provides more substrate for the liver to make the vitamin K–dependent clotting factors (II, VII, IX, X). Warfarin works by blocking this activation, so adding more vitamin K counters that effect and reduces the anticoagulated state. The result is a lower INR, meaning blood clotting ability moves closer to normal. In practice, consistent vitamin K intake is important because abrupt changes can alter INR and require dose adjustments.

Increasing vitamin K intake provides more substrate for the liver to make the vitamin K–dependent clotting factors (II, VII, IX, X). Warfarin works by blocking this activation, so adding more vitamin K counters that effect and reduces the anticoagulated state. The result is a lower INR, meaning blood clotting ability moves closer to normal. In practice, consistent vitamin K intake is important because abrupt changes can alter INR and require dose adjustments.