What is the toxic dose of vitamin D (Vitamin D) for infants?

Vitamin D Toxic Dose for Infants

The toxic dose of vitamin D for infants is 1,000 IU/day for infants 0-6 months and 1,500 IU/day for infants 7-12 months, as these are the established tolerable upper intake levels according to the Institute of Medicine 1.

Recommended vs. Toxic Doses

Safe Recommended Doses

• For healthy term infants 0-12 months: 400 IU/day 1, 2
• For preterm infants: 200-1000 IU/day (or 80-400 IU/kg/day) 3, 1

Tolerable Upper Intake Levels (Toxic Threshold)

• Infants 0-6 months: 1,000 IU/day 1
• Infants 7-12 months: 1,500 IU/day 1
• Children 1-3 years: 2,500 IU/day 1

Signs and Symptoms of Vitamin D Toxicity

Vitamin D toxicity in infants can manifest as:

• Hypercalcemia
• Hypercalciuria
• Nephrocalcinosis
• In severe cases: life-threatening symptoms 4, 5

Risk Factors for Vitamin D Toxicity

Several factors can increase the risk of vitamin D toxicity in infants:

1. Manufacturing errors: Cases of severe toxicity have been reported due to errors in manufacturing, formulation, or prescription 4, 5

   • One case report documented a supplement containing threefold higher vitamin D content (6,000 IU/drop) than listed on the label (2,000 IU/drop) 5

2. Dosing errors: Parental misunderstanding of dosing instructions can lead to significant overdosing 5

3. Special populations: Infants with liver or kidney disease may have altered vitamin D metabolism and require special attention 1, 2

Monitoring Recommendations

• The Drugs and Therapeutics Committee of the Pediatric Endocrine Society suggests monitoring serum 25-hydroxyvitamin D levels in infants receiving long-term supplementation at or above the upper intake levels 4
• Routine monitoring is not necessary for healthy term infants receiving appropriate supplementation (400 IU/day) 1

Case Reports of Toxicity

• A case report documented vitamin D toxicity in a 4-month-old exclusively breastfed infant who received approximately 50,000 IU/day for two months due to a combination of overdosing and higher-than-labeled vitamin D content in the supplement 5
• Another case report documented vitamin D intoxication in a 7-month-old infant even with recommended daily doses, suggesting individual susceptibility may vary 6

Prevention of Vitamin D Toxicity

To prevent vitamin D toxicity in infants:

1. Use only regulated, pharmaceutical-grade vitamin D supplements for infants
2. Follow exact dosing instructions (typically 400 IU/day)
3. Avoid using multiple vitamin D-containing products simultaneously
4. Be cautious with extremely concentrated formulations
5. Consider monitoring vitamin D levels in infants receiving doses at or above the upper intake level 4

Clinical Implications

While vitamin D supplementation at 400 IU/day has a long history of safety in infants 1, 7, clinicians should be aware that:

• Vitamin D is fat-soluble and cannot be readily excreted from the body 6
• Higher doses have not been consistently shown to provide additional clinical benefits for healthy infants 2
• Vitamin D toxicity, although rare, can present with severe and potentially life-threatening symptoms 4, 5

The evidence clearly supports maintaining vitamin D supplementation within the recommended range of 400 IU/day for healthy term infants and avoiding doses that exceed the established tolerable upper intake levels.