Davis's Lab & Diagnostic Tests

Osmolality, Blood and Urine

Osmolality, Blood and Urine is a topic covered in the Davis's Lab & Diagnostic Tests.

To view the entire topic, please or purchase a subscription.

Davis’s Laboratory and Diagnostic Tests Online, powered by Unbound Medicine, provides nurses and students access to 400+ test monographs containing reference ranges, indications, patient preparation and result interpretation. Explore these free sample topics:


-- The first section of this topic is shown below --



Common Use:
To assess fluid and electrolyte balance related to hydration, acid-base balance, and screening for toxins.

Serum collected in a gold-, red-, or red/gray-top tube; urine from an unpreserved random specimen collected in a clean plastic collection container.

Normal Findings:
(Method: Freezing point depression)

Conventional UnitsSI Units (Conventional Units × 1)
Serum275–295 mOsm/kg275–295 mmol/kg
Urine (random)50–1200 mOsm/kg50–1200 mmol/kg
Urine (24-hr collection)
 Newborn75–300 mOsm/kg75–300 mmol/kg
 Children and adults250–900 mOsm/kg250–900 mmol/kg

-- To view the remaining sections of this topic, please or purchase a subscription --