how are they related to warfarin therapy?
The proper anticoagulant action of the anticoagulant drug warfarin is a function of vitamin K intake and drug dose, and due to differing absorption must be individualized for each patient.
Vitamin K
The proper anticoagulant action of the anticoagulant drug warfarin is a function of vitamin K intake and drug dose, and due to differing absorption must be individualized for each patient. 
what organ contains bacteria that help produce vitamin k The large intestine what vitamin is this? Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. can you name some foods where it is found? Green leafy vegetables how are they medically used? Vitamin K is also part of the suggested treatment regime for poisoning by rodenticide
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Vitamin K [SEP] Managing warfarin therapy
The proper anticoagulant action of the anticoagulant drug warfarin is a function of vitamin K intake and drug dose, and due to differing absorption must be individualized for each patient. Vitamin K is a treatment for bleeding events caused by overdose of the drug. The vitamin can be administered by mouth, intravenously or subcutaneously. Oral vitamin K is used in situations when a person's International normalised ratio is greater than 10 but there is no active bleeding. The newer anticoagulants apixaban, dabigatran and rivaroxaban are not vitamin K antagonists.