International units per milliliter (IU/mL)
An international unit is an arbitrary amount of a substance agreed upon by scientists and doctors. A milliliter is a measure of volume that is equal to one-thousandth of a liter (or slightly less than a quarter of a teaspoon).
Some medical tests report results using international units (IU) per milliliter (mL).
Current as of: May 1, 2026
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