Vitamin A Dosage for Children
For parenteral nutrition, preterm infants should receive 700-1500 IU/kg/day, term infants 150-300 μg/kg/day (or 2300 IU/day), and children 1-18 years should receive 150 μg/day, with vitamin A administered with lipid emulsion whenever possible to minimize losses. 1
Age-Specific Dosing for Parenteral Nutrition
Preterm Infants
- Recommended dose: 700-1500 IU/kg/day (227-455 μg/kg/day) 1
- This higher dose accounts for increased needs and substantial losses during administration 1
- Vitamin A supplementation in very low birth weight infants reduces death or oxygen requirement at one month and decreases chronic lung disease risk 1
Term Infants (0-12 months)
- Recommended dose: 150-300 μg/kg/day or 2300 IU/day (697 μg/day) 1
- This provides adequate vitamin A for normal growth, vision, immune function, and epithelial cell maintenance 1
Children and Adolescents (1-18 years)
- Recommended dose: 150 μg/day 1
- This flat dose reflects decreased per-kilogram requirements with age 1
Critical Administration Considerations
Delivery Method
- Vitamin A should be given with lipid emulsion whenever possible to reduce losses from photo-degradation and adsorption 1
- When given with water-soluble solutions, only 40% or less of the intended dose may actually be delivered due to tubing adsorption 1
- Retinyl palmitate adsorbs to tubing less than retinol and is preferred for parenteral administration 1
Monitoring Parameters
- Target serum retinol levels:
- Under stress conditions, use retinol-binding protein (RBP)/transthyretin ratio instead of serum retinol 1
Oral Supplementation for Deficiency Prevention
Community Settings (Developing Countries)
- Infants 0-6 months: Three doses of 50,000 IU given with routine vaccines 2
- Children 6-59 months: Periodic high-dose supplementation in populations with documented vitamin A deficiency 2, 3
- This reduces all-cause mortality by 12% and diarrhea mortality by 12% in deficient populations 3
Dietary Reference Intakes (Well-Nourished Populations)
- 7-36 months: 250 μg retinol equivalents (RE)/day 4
- 15-17 years: 750 μg RE/day 4
- These intakes are usually adequate in industrialized countries 4
Safety Thresholds and Toxicity
Acute Toxicity
- Occurs with single doses >150,000 μg (approximately 500,000 IU in adults) 1, 5
- Symptoms include increased intracranial pressure, headache, nausea, vomiting, vertigo, and blurred vision 1
Chronic Toxicity
- Occurs with prolonged intake of approximately 30,000 μg/day 1
- Manifestations include bone abnormalities, fractures, dermatitis, alopecia, hepatocellular necrosis, and hyperlipidemia 1
- There is a relatively narrow window between deficiency and toxicity 1
Upper Limits for Infants
- Non-breastfed infants may exceed the upper limit of 600 μg/day with some formulas, though new European regulations (2015) aim to limit this 4
Clinical Conditions Requiring Increased Monitoring
High-risk conditions for vitamin A deficiency include: 1
- Infection (sepsis, HIV)
- Burns and mechanical ventilation
- Hepatobiliary dysfunction or renal failure
- Malabsorption (abetalipoproteinemia, cystic fibrosis)
- Protein-energy malnutrition
- Zinc deficiency
- Hematologic/oncologic conditions
Common Pitfalls to Avoid
- Do not administer vitamin A with water-soluble vitamin solutions when lipid emulsion is available, as this results in >60% loss of intended dose 1
- Do not rely on serum retinol levels during acute illness as they are unreliable under stress conditions 1
- Do not use beta-carotene or food fortification doses to calculate parenteral requirements, as bioconversion efficiency varies widely (3.6:1 to 28:1) 1
- Monitor for toxicity in patients with liver or renal disorders receiving intravenous vitamin A, as they have increased risk 1