Menaquinone-7
Menaquinone-7 is a long-acting form of vitamin K2, a fat-soluble vitamin available without prescription. Vitamin K acts as a cofactor for the enzyme that activates certain proteins, including osteocalcin in bone and the clotting factors made in the liver. It is taken mainly in the context of bone health.
Because it is fat-soluble, absorption is markedly better when it is taken with a meal that contains some fat rather than on an empty stomach. The important interaction is with warfarin: warfarin works by blocking vitamin K recycling, so added vitamin K directly opposes it and can shift INR out of range, which is why the two are not combined. Anyone already on warfarin or another vitamin K antagonist should not add this supplement without the prescriber knowing.
See a doctor before starting it while on warfarin or any anticoagulant, and see a doctor promptly if unusual bruising, prolonged bleeding, or an unexpected change in INR appears after it has been added.
Reference information, not medical advice. Discuss any change with your doctor.