Osmolality, Urine

This is a urine test that measures the amount of dissolved particles in a solution. If there are more dissolved particles in your urine, the osmolality would be increased. This is a measurement for an accurate check on the concentrating ability of the kidney. This is also used to monitor fluid and electrolyte balance in the urine. The electrolytes are the particles or ions in your urine.

PREPARATION FOR TEST

No preparation or fasting is necessary.

NORMAL FINDINGS

  • 12- to 14-hour fluid restriction: greater than 850 mOsm/kg H2O (SI units)

  • Random specimen: 50-1200 mOsm/kg H2O, depending on fluid

  • Intake or 50-1200 mmol/kg (SI units)

Ranges for normal findings may vary among different laboratories and hospitals. You should always check with your doctor after having lab work or other tests done to discuss the meaning of your test results and whether your values are considered within normal limits.

MEANING OF TEST

Your caregiver will go over the test results with you and discuss the importance and meaning of your results, as well as treatment options and the need for additional tests if necessary.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.