What are the guidelines for vitamin D3 supplementation in children?

Guidelines for Vitamin D3 Supplementation in Children

Healthy children should receive 400 IU/day of vitamin D3 during the first year of life and 600 IU/day from ages 1-18 years to maintain optimal vitamin D status and prevent deficiency. 1, 2

Recommended Daily Dosages by Age Group

• Infants (0-12 months): 400 IU/day of vitamin D3 1, 2
• Children (1-18 years): 600 IU/day of vitamin D3 1
• Preterm infants on parenteral nutrition: 200-1000 IU/day (or 80-400 IU/kg/day) 3
• Term infants up to 12 months on parenteral nutrition: 400 IU/day (or 40-150 IU/kg/day) 3
• Older children on parenteral nutrition: 400-600 IU/day 3

Vitamin D Status Classification and Treatment

• Vitamin D deficiency: 25(OH)D level <20 ng/mL 1
  • Severe deficiency (<5 ng/mL): Higher replacement doses required 3
  • Mild deficiency (5-15 ng/mL): Requires therapeutic supplementation 3
• Vitamin D insufficiency: 25(OH)D level 21-29 ng/mL 1
• Target level: ≥30 ng/mL (75 nmol/L) to prevent secondary hyperparathyroidism 4

Supplementation Strategies for Deficiency/Insufficiency

• For vitamin D deficiency: Higher doses are required for repletion 3
  • Daily doses of 1500-2000 IU/day have been shown effective in North Italian children 5
  • For obese children with deficiency, higher loading doses (25,000 IU weekly for 9 weeks) have been shown effective and well-tolerated 6
• For maintenance after repletion: 200-1000 IU/day 3
• Seasonal supplementation: In northern latitudes, supplementation with 1500 IU/day from November to April may be appropriate 5

Special Populations

• Children with CKD (Chronic Kidney Disease):

  • Monitor 25(OH)D levels annually 3
  • Supplement with vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol) to correct deficiency 3
  • Vitamin D3 appears to have higher bioefficacy than vitamin D2 3
  • Monitor calcium and phosphorus levels one month after initiating or changing vitamin D dose 3

• Children with nephrotic syndrome:

  • Higher doses may be required due to urinary losses of vitamin D-binding protein 3
  • Close monitoring of ionized calcium, 25-OH-D3, and PTH levels is recommended 3

• Non-white children:

  • May require higher doses due to increased risk of deficiency (3x higher probability of deficiency despite standard supplementation) 5

• Obese children:

  • Standard doses may be inadequate; higher loading doses may be required 6
  • Weekly dosing (25,000 IU/week) has been shown effective in achieving sufficiency 6

Monitoring Recommendations

• Routine monitoring of 25(OH)D levels is not necessary in healthy children receiving appropriate supplementation 3
• Annual monitoring is recommended for:
  • Children with CKD 3
  • Children on long-term parenteral nutrition 3
  • Children with risk factors for vitamin D deficiency 4
• Monitor calcium and phosphorus one month after initiating or changing vitamin D dose in children with CKD 3

Clinical Considerations and Pitfalls

• Cholecalciferol (D3) appears to have higher bioefficacy than ergocalciferol (D2), though long-term comparative trials in humans are lacking 3
• Vitamin D deficiency in children can lead to growth failure and rickets if left untreated 1, 2
• Calcitriol, alfacalcidol, or other synthetic active vitamin D analogs should not be used to treat nutritional vitamin D deficiency 3
• Adolescents may require higher doses than younger children to achieve vitamin D sufficiency 5
• Decreased sunlight exposure increases children's risk of vitamin D deficiency 2

By following these guidelines, clinicians can effectively prevent and treat vitamin D deficiency in children, optimizing bone health and potentially reducing the risk of other chronic diseases associated with vitamin D deficiency.