Vitamin K1

Vitamin K1, also called phylloquinone or phytonadione, is a fat soluble vitamin. Phylloquinone is a cofactor of the enzyme γ-carboxylase, which modifies and activates precursors to coagulation factors II, VII, IX, and X. It is indicated in the treatment of coagulation disorders due to faulty formation of coagulation factors II, VII, IX, and X caused by deficiency or interference in the activity of vitamin K.

Phylloquinone has been synthesized since at least 1939, and was approved by the FDA prior to 1955.

Oral phylloquinone is indicated to treat prothrombin deficiency caused by coumarin or indanedione derivatives; and hypoprothrombinemia secondary to antibacterial therapy, salicylates, or obstructive jaundice or biliary fistulas with concomitant bile salt administration.

Parenteral (intravenous, intramuscular, and subcutaneous) phylloquinone is indicated to treat coagulation disorders due to faulty formation of coagulation factors II, VII, IX, and X caused by vitamin K deficiency or some interference with vitamin K activity. These indications include the above indications as well as hypoprothrombinemia secondary to sprue, ulcerative colitis, celiac disease, intestinal resection, pancreatic cystic fibrosis, or regional enteritis; or hypoprothrombinemia caused by interference with vitamin k metabolism.