What is the recommended daily dose of vitamin A (Vitamin A) for infants based on their weight?

Weight-Based Vitamin A Dosing for Infants

For preterm infants on parenteral nutrition, administer 700-1500 IU/kg/day (227-455 µg/kg/day) of vitamin A mixed with lipid emulsion, while term infants up to 12 months require 150-300 µg/kg/day or a fixed dose of 2300 IU/day (697 µg/day). 1, 2

Preterm Infants (<37 weeks gestation)

Parenteral nutrition dosing:

• 700-1500 IU/kg/day (227-455 µg/kg/day) is the recommended range for preterm infants receiving intravenous nutrition 1, 2
• This must be administered with lipid emulsion, not water-based solutions, as more than 60% of vitamin A is lost when given in aqueous preparations 1, 2
• The higher end of this range (closer to 1500 IU/kg/day) should be targeted for very low birth weight infants (<1500g) and those at risk for bronchopulmonary dysplasia 2

Critical administration details:

• Start vitamin A supplementation as early as day 2 of life when intravenous lipids are initiated 3
• Retinyl palmitate is the preferred formulation as it adsorbs less to tubing compared to retinol 1
• Polyethylene (PE) tubing is preferable to polyurethane "micro tubing" which causes greater lipophilic substance adsorption 1

Term Infants (0-12 months)

Weight-based dosing:

• 150-300 µg/kg/day for infants up to 12 months of age 1, 2
• Alternatively, a fixed dose of 2300 IU/day (697 µg/day) can be used for term infants 1, 2

Practical conversion:

• 1 µg retinol activity equivalent (RAE) = 1 µg all-trans retinol = 3.33 IU vitamin A 1

Monitoring and Deficiency Thresholds

Serum vitamin A levels indicating deficiency:

• Below 200 µg/L (0.70 µmol/L) indicates vitamin A deficiency and insufficient intake 2, 4
• Below 100 µg/L (0.35 µmol/L) indicates severe deficiency with depleted liver stores 2
• Above 300 µg/L (1.05 µmol/L) indicates adequate vitamin A status 4

When to monitor:

• Routine monitoring is not recommended except for infants on long-term parenteral nutrition 2, 5
• Consider monitoring in high-risk populations: sepsis, HIV infection, burns, mechanical ventilation, steroid use, hepatobiliary dysfunction, renal failure, or hemato-oncologic diseases 2

Special Considerations for Very Low Birth Weight Infants

Enhanced supplementation protocols:

• For infants <1500g with significant lung disease, consider the higher end of the dosing range (1500 IU/kg/day) 3
• Studies show that even with supplementation of 5000 IU three times weekly (in addition to standard parenteral and enteral intake), 32% of premature infants still had serum levels below 200 µg/L 1
• A modified regimen with vitamin A increased by 35% and premixed with lipid emulsion achieved higher plasma concentrations in very low birth weight infants 1

Toxicity Warning

Narrow therapeutic window:

• Vitamin A has a relatively narrow margin between deficiency and toxicity 1, 2
• Acute toxicity (>150,000 µg single dose) presents with increased intracranial pressure, headache, nausea, vomiting, vertigo, and blurred vision 1, 2
• Chronic toxicity (approximately 30,000 µg/day) causes bone abnormalities, dermatitis, alopecia, ataxia, muscle pain, hepatocellular necrosis, and hyperlipidemia 1, 2
• Toxicity risk is higher in patients with liver and renal disorders 1

Common Pitfalls to Avoid

• Never use adult multivitamin formulations in infants due to propylene glycol and polysorbate toxicity 5, 6
• Do not administer vitamin A in water-based solutions during parenteral nutrition—losses exceed 60% 1, 2
• Do not delay initiation—vitamin A supplementation should begin by day 2 of life in preterm infants 3
• Avoid once-weekly dosing regimens (15,000 IU weekly)—this worsens vitamin A deficiency compared to standard three-times-weekly protocols 1, 7