Can vitamin K (Vitamin K1, phytonadione) be administered 8 hours after birth?

Administration of Vitamin K at 8 Hours After Birth

Yes, vitamin K (phytonadione) can be administered 8 hours after birth, though ideally it should be given within the first hour of birth for optimal prophylaxis against vitamin K deficiency bleeding.

Timing of Vitamin K Administration

• According to the American Academy of Pediatrics (AAP), while vitamin K administration is ideally recommended within one hour of birth, it can be delayed for at least 1 hour and up to 4 hours after delivery to accommodate skin-to-skin contact and the first breastfeeding session 1
• The FDA label for phytonadione indicates that a single intramuscular dose of 0.5 to 1 mg should be given within one hour of birth, but does not specifically contraindicate later administration 2
• The Canadian Paediatric Society recommends administration within 6 hours after birth for all healthy term infants 3

Administration Routes and Dosing

• Intramuscular (IM) administration is the preferred route for efficiency and reliability 4

  • Recommended dose: 1 mg IM as a single dose 2, 4
  • This route provides the most reliable protection against all forms of vitamin K deficiency bleeding (VKDB), including late VKDB 4, 5

• If oral administration is chosen at this point (8 hours after birth), the following regimens are recommended:

  • Either 3 × 2 mg vitamin K1 orally (at this time, at 4-6 days, and at 4-6 weeks) 4
  • Or 2 mg vitamin K1 orally now, followed by weekly doses of 1 mg for 3 months 4

Special Considerations

• For infants whose mothers have taken medications that interfere with vitamin K metabolism, intramuscular administration is strongly recommended 2, 4
• The oral route is not appropriate for:
  • Preterm infants
  • Newborns with cholestasis or impaired intestinal absorption
  • Infants too unwell to take oral vitamin K1 4

Documentation and Follow-up

• The date, dose, and mode of administration should be clearly documented 4
• If using the oral route and the infant vomits or regurgitates within 1 hour of administration, repeating the dose is appropriate 4
• For exclusively breastfed infants, follow-up doses are crucial if using the oral route, as a single oral dose does not provide adequate protection against late VKDB 4, 5

Clinical Implications of Delayed Administration

• While administration at 8 hours is later than optimal, providing vitamin K at this time is still beneficial and necessary for preventing VKDB 5, 6
• The risk of early VKDB (occurring in the first 24 hours) may not be completely eliminated if administration is delayed to 8 hours, especially in infants of mothers taking drugs that inhibit vitamin K 5, 6
• Classic VKDB (occurring in the first week) can still be effectively prevented with administration at 8 hours 5

Remember that while administration at 8 hours is not ideal, it is significantly better than no prophylaxis at all, and should be provided to prevent the potentially serious consequences of vitamin K deficiency bleeding.