Skip to main content

vitamin k2 and warfarin

K2 also reverses warfarin's effect

What's happening

MK-4 and MK-7 forms of vitamin K2 can interfere with warfarin. MK-7 has a longer half-life (~3 days) and may cause more sustained INR changes than K1. Even low doses can affect clotting.

Recommendation

Avoid vitamin K2 supplements on warfarin. If prescribed, requires frequent INR monitoring.

Timing

Avoid combination entirely

Sources

  • — Thrombosis and Haemostasis
  • — PMID: 17138823

Frequently Asked Questions

Can I take vitamin k2 and warfarin together?

K2 also reverses warfarin's effect. Avoid vitamin K2 supplements on warfarin. If prescribed, requires frequent INR monitoring.

How should I time vitamin k2 and warfarin?

Avoid combination entirely

Is this interaction dangerous?

This interaction is rated “Danger” by Formulate. MK-4 and MK-7 forms of vitamin K2 can interfere with warfarin. MK-7 has a longer half-life (~3 days) and may cause more sustained INR changes than K1. Even low doses can affect clotting.

Want to check your whole stack?

The free checker lets you add any combination of supplements and medications at once. Formulate's desktop app goes further — every stack change surfaces interaction alerts automatically.

Open the checkerGet the desktop app

Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.