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Osmolality test

Osmolality test

Overview

An osmolality urine test is performed to measure the concentration of particles in urine. Greater than normal results may indicate conditions such as Addison disease, congestive heart failure or shock. Lower-than-normal measurements may indicate aldosteronism, diabetes insipidus, excess fluid intake, renal tubular necrosis or severe pyelonephritis.

Review Date 8/20/2023

Updated by: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.