Vitamin K (Phytomenadione)
BASICS: DOSAGE:
• Warfarin antagonist • 1mg in 0.1ml for IM dose at birth
• Prevention of vitamin K deficiency + • 2mg in 0.2ml orally at birth, 2nd dose of
Haemorrhagic disease of the newborn 2mg orally at 4-7 days old
• POM, midwives exemptions • If exclusively breastfed - 3rd dose of 2mg
orally at 1 month old
• IM injection or Oral
SIDE EFFECTS: INTERACTIONS:
• Anaphylactoid reactions after IV injections • Anticoagulants - antagonism of the
• Rarely, venous irritation or phlebitis anticoagulant effect
PHARMACODYNAMICS:
• Synthetic vitamin K, vit K needed for the
production of prothrombin, factor X,
factor VII, factor IX
• Absorbed into muscle - directly into systemic
circulation, metabolised in liver + GI tract,
eliminated in the urine and bile acids
FETAL RISK: GUIDANCE:
• Poor placental transfer • All parents of neonates should be offered
at birth
• No risk data available
BREASTFEEDING:
• Maternal doses - not enough information
available to allow classification as safe
drug
• Large maternal doses of anticoagulants
may require neonatal vitamin K
BASICS: DOSAGE:
• Warfarin antagonist • 1mg in 0.1ml for IM dose at birth
• Prevention of vitamin K deficiency + • 2mg in 0.2ml orally at birth, 2nd dose of
Haemorrhagic disease of the newborn 2mg orally at 4-7 days old
• POM, midwives exemptions • If exclusively breastfed - 3rd dose of 2mg
orally at 1 month old
• IM injection or Oral
SIDE EFFECTS: INTERACTIONS:
• Anaphylactoid reactions after IV injections • Anticoagulants - antagonism of the
• Rarely, venous irritation or phlebitis anticoagulant effect
PHARMACODYNAMICS:
• Synthetic vitamin K, vit K needed for the
production of prothrombin, factor X,
factor VII, factor IX
• Absorbed into muscle - directly into systemic
circulation, metabolised in liver + GI tract,
eliminated in the urine and bile acids
FETAL RISK: GUIDANCE:
• Poor placental transfer • All parents of neonates should be offered
at birth
• No risk data available
BREASTFEEDING:
• Maternal doses - not enough information
available to allow classification as safe
drug
• Large maternal doses of anticoagulants
may require neonatal vitamin K
