At a Glance
Why Get Tested?
To help detect, diagnose, and determine the cause of antidiuretic hormone (ADH) deficiency or excess; to investigate low blood sodium levels (hyponatremia); to distinguish between the two types of diabetes insipidus
When to Get Tested?
When you have low blood sodium or have persistent thirst, frequent urination, and dehydration
A blood sample drawn from a vein in your arm
Test Preparation Needed?
None needed for an ADH test; however, talk to your health care provider about required preparation when the ADH test is performed as part of a water deprivation ADH stimulation test or a water loading ADH suppression test.