Volume Conversion for 400 IU Vitamin D Supplementation
The volume in milliliters depends entirely on the concentration of the specific vitamin D3 product you are using, as different formulations contain different amounts of IU per drop or per mL.
Understanding the Calculation
- Most commercially available infant vitamin D3 drops in the United States contain 400 IU per 1 mL (or per single drop, depending on the dropper design). 1
- If your product contains 400 IU per 1 mL, then 400 IU/day = 1 mL daily. 1
- Some concentrated formulations may contain 400 IU in just 0.5 mL or even in a single drop (approximately 0.05 mL), while others may require multiple drops to reach 400 IU. 1
Critical Steps to Determine the Correct Volume
- Always check the product label for the exact concentration (IU per mL or IU per drop) before administering. 1
- Use the dropper or measuring device provided with the specific product to ensure accurate dosing. 1
- Calculate the volume using the formula: Volume (mL) = Desired dose (400 IU) ÷ Concentration (IU per mL). 1
Standard Dosing Recommendation for Term Infants
- All term infants should receive 400 IU of vitamin D3 daily starting at hospital discharge, regardless of whether they are breastfed or formula-fed. 2, 1
- This dose is adequate to prevent vitamin D deficiency and rickets in healthy term infants. 2, 3
- Cholecalciferol (vitamin D3) is the preferred formulation over ergocalciferol (vitamin D2) due to higher bioavailability. 1, 4
Common Pitfalls to Avoid
- Do not assume all vitamin D drops have the same concentration—verify the product label every time. 1
- Avoid extremely concentrated high-dose formulations intended for adults, as accidental overdosing can occur. 3
- Do not delay supplementation while waiting for the first outpatient visit—begin at hospital discharge. 1
- For formula-fed infants, continue 400 IU/day supplementation until the infant consistently consumes at least 28 ounces (approximately 840 mL) of vitamin D-fortified formula daily. 1