PHYTOMENADIONE

Vitamin K1, Konakion® MM Paediatric

Reviewed by Brenda Hughes (Pharmacy), Dr Simon Rowley, Dr Carl Kuschel, and Helen Lamb (NSANP)
February 2007
Administration Newborn Drug Protocol Index Newborn Services Home Page

Dose and Administration

Prophylaxis

  1. Term infant
    1. Intramuscluar injection 0.5-1mg IM at birth (preferred route)
    2. Oral administration
      • 2mg oral soon after birth, then
      • 2mg oral at 3-7 days, then
      • 2mg oral at 6 weeks
      Note:
      • If the oral dose is vomited or regurgitated within one hour, a repeat dose should be given.
      • When this preparation is prescribed orally the second and third doses may need to be administered after the baby has been discharged from hospital.
      • It is the responsibility of the LMC and parents to ensure that subsequent doses are administered.

    See the Vitamin K guideline for information on the risks of Vitamin K Deficiency Bleeding (VKDB).

  2. Preterm infant <1.5kg
    1. 0.5mg IM at birth

Treatment of Vitamin K Deficiency Bleeding 1

  1. Intravenous 1 mg, repeated 8 hourly if necessary. Administer slowly.

Indications

  1. Prophylaxis of Vitamin K Deficiency Bleeding (VKDB).
  2. Treatment of VKDB or neonatal hypoprothrombinaemia.

Contraindications

  1. Lack of parental consent (see Vitamin K guideline).

Precautions

  1. Delay IM administration in infants at risk of HIV and haemophilia as per guidelines.
  2. Severe hepatic dysfunction.
  3. Bleeding disorders that are not vitamin K dependent.
  4. Parenteral administration may increase risk of kernicterus.2

Drug Interactions 3

Gentamicin: possible decrease in efficacy of IV vitamin K.

Clinical Pharmacology 2

Phytomenadione (synthetic Vitamin K1), part of the hepatic carboxylase system, is essential for the formation of clotting factors II (prothrombin), VII, IX, and X, plus the clotting inhibitor proteins C and S.  Lack of vitamin K results in an increased potential for haemorrhage.  This can be reversed by the administration of vitamin K.

In Konakion MM paediatric ampoules, the vitamin K is contained in a physiological system of bile acid-lecithin micelles which result in a improved local and systemic tolerance than previous injection solutions.

Given orally, the vitamin K is absorbed mainly from the middle of the small intestine.  Absorption is enhanced by the presence of bile and pancreatic juice; absorption is impaired by short bowel syndrome, biliary atresia, pancreatic insufficiency, and malabsorption syndromes. Systemic availability is approximately 50%, with wide inter-patient variability.

Vitamin K is eliminated by metabolic glucuronidation and sulphation.  The half life is 1.5 to 3 hours (adults).

Possible Adverse Effects 2

  1. Anaphylactoid reaction.
  2. Local irritation possible, but is rare.

Special Considerations

  1. Konakion MM® Paediatric is licensed for oral and parenteral administration.
  2. Intravenous administration should be reserved for potentially fatal haemorrhage.
  3. Prothrombin synthesis takes up to 2 hours to occur following parenteral administration of vitamin K.
  4. Efficacy of treatment with vitamin K is decreased with liver disease.