2 hours
Test Updated:
OSMOLALITY, URINE
OSMOU
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Test Overview
Freezing Point
To aid in evaluation of water balance and kidney function.
300 - 1300 mOsm/kg for random specimens
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect 24 hour urine specimen with no preservative. Aliquot 2 mL into a plastic urine container and refrigerate. Record total 24 hour urine volume and collection dates/times on request form. Random urine is also acceptable.