vitamin K-1, phytonadione (Mephyton) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Other side effects reported with use of injectable phytonadione include:

Hyperbilirubinemia (high levels of bilirubin in the blood), a byproduct of red blood cell breakdown, has been reported in newborns following administration of injectable phytonadione.




  • Oral tablets: 5 mg, 100 mcg
  • Solution for injection: 10 mg/ml, 1 mg/0.5 ml

STORAGE: Tablets should be stored at room temperature between 15 C and 30 C (59 F and 86 F). Injectable vitamin K should be stored in original container at controlled room temperature between 20 C and 25 C (68 F and 77 F), and should be protected from light.


Oral vitamin K in Adults

  • For the treatment of anticoagulant-induced prothrombin deficiency: The initial recommended dose is 2.5 mg to 10 mg or up to 25 mg by mouth (rarely 50 mg).
  • For the treatment of hypoprothrombinemia due to other causes: the initial recommended dose is 2.5 mg to 25 mg or more (rarely up to 50 mg).
  • For the treatment of bleeding or bleeding prophylaxis in patients with warfarin toxicity: Adults with INR > 10 with no significant bleeding: administer 2.5-5 mg by mouth. Hold warfarin therapy.
  • Adults with serious bleeding at any elevation of INR: administer 5-10 mg intravenously by slow infusion in combination with 4-factor prothrombin complex concentrate. Hold warfarin therapy.
  • For the treatment of hemorrhagic disease of the newborn: administer 1 mg/dose/day intramuscularly (into the muscle) or subcutaneously (into the fatty tissue). Higher doses may be required if mother has been receiving treatment with oral anticoagulants.
  • For the prevention of hemorrhagic disease of the newborn: administer 0.5-1 mg intramuscularly within 1 hour of birth.
Medically Reviewed by a Doctor on 6/12/2015

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