What is the recommended vitamin K dosing regimen for newborns at risk of vitamin K deficiency, single dose or multiple dose?

Vitamin K Dosing Regimen for Newborns at Risk of Vitamin K Deficiency

The recommended vitamin K dosing regimen for newborns at risk of vitamin K deficiency is a single intramuscular dose of 0.5-1 mg vitamin K1 within one hour of birth, as this is the most effective and reliable method of preventing vitamin K deficiency bleeding (VKDB). 1, 2

Evidence-Based Recommendations

Primary Recommendation

• Intramuscular (IM) administration is the preferred route for efficiency and reliability of administration 2
• A single IM dose of 0.5-1 mg vitamin K1 should be given within one hour of birth 1, 2
• The American Academy of Pediatrics and FDA recommend this approach as the gold standard for VKDB prevention 1

Alternative Oral Regimens

If parents decline IM administration, oral regimens may be considered, though they are less effective:

• Option 1: 3 × 2 mg vitamin K1 orally at birth, at 4-6 days, and at 4-6 weeks 2
• Option 2: 2 mg vitamin K1 orally at birth, followed by weekly doses of 1 mg for 3 months 2

Comparative Efficacy of Different Regimens

• Single IM injection (0.5-1 mg) provides superior protection against all forms of VKDB (early, classic, and late) 2, 3
• Oral regimens effectively prevent early and classic VKDB but are less effective against late VKDB 4
• A study comparing different regimens in infants with biliary atresia (at high risk for VKDB) found:
  • Daily oral dose of 25 μg failed to prevent bleeding 5
  • Weekly oral dose of 1 mg offered significantly higher protection 5
  • IM prophylaxis of 2 mg at birth was most effective 5

Special Considerations

High-Risk Newborns

• For preterm infants, those with cholestasis, impaired intestinal absorption, or those too unwell to take oral vitamin K1, the IM route is mandatory 2
• For infants whose mothers have taken medications that interfere with vitamin K metabolism (anticonvulsants, anticoagulants, antituberculosis drugs), IM administration is essential 6, 2

Monitoring

• Classical coagulation tests (PT, PTT) can be used in low-risk infants for indirect evaluation of vitamin K status 6
• PIVKA-II (Protein Induced by Vitamin K Absence) is a more useful biomarker of subclinical vitamin K deficiency for at-risk patient groups 6

Implementation Considerations

• The date, dose, and mode of administration should be documented 2
• If an infant vomits or regurgitates an oral dose within 1 hour of administration, repeating the dose may be appropriate 2
• Parental refusal of vitamin K prophylaxis should be documented due to the increased risk of VKDB 2
• Parents who receive prenatal education about vitamin K prophylaxis may be more likely to comply with recommendations 2

Pitfalls and Caveats

• The success of oral regimens depends heavily on compliance, which may vary between populations and healthcare settings 2
• Single oral doses are insufficient to prevent late VKDB 4
• Formula-fed infants are at lower risk for VKDB than exclusively breastfed infants, but still require prophylaxis 4, 5
• Vitamin K deficiency can lead to serious consequences including intracranial hemorrhage if prophylaxis is inadequate 1, 4