At a Glance
Why Get Tested?
To help detect, diagnose, and determine the cause of antidiuretic hormone (ADH) deficiency or excess. However, this test is not widely used; diagnoses of conditions of ADH excess/ deficiency are usually based on clinical history and other laboratory tests, such as blood and urine osmolality as well as electrolytes.
When to Get Tested?
ADH may be requested if results of initial investigations of ADH deficiency/ excess are equivocal. However, ADH analysis is rarely required.
A blood sample taken from a vein in your arm
Test Preparation Needed?
Alcohol and some medications (including diuretics) can interfere with ADH secretion or its action. Talk to your doctor to identify any medications that should be discontinued before the test.
An ADH test may be requested as part of a water deprivation test. Talk to your doctor to determine if any preparation is required for this test.