التداخل بين فيتامين ك ووارفارين

فيتامين ك يقلّل الأثر المضاد للتخثر لوارفارين؛ والتغيّرات المفاجئة في المتناول منه من المكملات أو النظام الغذائي قد تخلّ بقيمة INR.

النص الأصلي للنشرة (بالإنجليزية) Vitamin K reduces the anticoagulant effect of warfarin; sudden changes in intake from supplements or diet can throw off INR.

Polycythemia vera Vasculitis Diabetes mellitus 5.9 Endogenous Factors Affecting INR The following factors may be responsible for increased INR response: diarrhea, hepatic disorders, poor nutritional state, steatorrhea, or vitamin K deficiency.

The following factors may be responsible for decreased INR response: increased vitamin K intake or hereditary warfarin resistance.

Pharmacodynamic mechanisms for drug interactions with warfarin sodium are synergism (impaired hemostasis, reduced clotting factor synthesis), competitive antagonism (vitamin K), and alteration of the physiologic control loop for vitamin K metabolism (hereditary resistance).

The amount of vitamin K in food may affect therapy with warfarin sodium.

Advise patients taking warfarin sodium to eat a normal, balanced diet maintaining a consistent amount of vitamin K.