Antidiuretic hormone blood test
The antidiuretic blood test measures the level of antidiuretic hormone (ADH) in blood.
How the Test is Performed
Blood sample is needed
Venipuncture is the collection of blood from a vein. It is most often done for laboratory testing.
Read Article Now Book Mark ArticleHow to Prepare for the Test
Talk to your health care provider about your medicines before the test. Many medicines can affect ADH level, including:
- Alcohol
- Diuretics (water pills)
- Blood pressure medicines
- Insulin
- Medicines for mental disorders
- Nicotine
- Steroids
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.
Why the Test is Performed
ADH is a hormone that is produced in a part of the brain called the hypothalamus. It is then stored and released from the pituitary, a small gland at the base of the brain. ADH acts on the kidneys to regulate the amount of water excreted in the urine.
Hypothalamus
The hypothalamus is an area of the brain that produces hormones that regulate:Body temperatureHeart rateHungerMoodRelease of hormones from many gland...
Read Article Now Book Mark ArticleThe ADH blood test is ordered when your provider suspects you have a disorder that may be due to an abnormal ADH level such as:
- Buildup of fluids in your body that are causing swelling or puffiness (edema)
Edema
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
Read Article Now Book Mark Article - Excessive amounts of urine
- Low sodium (salt) level in your blood
- Thirst that is intense or uncontrollable
Certain diseases affect the normal release of ADH. The blood level of ADH must be tested to determine the cause of the disease. ADH may be measured as part of a water restriction test to find the cause of a disease.
Normal Results
Normal values for ADH can range from 0 to 5.9 pg/mL (0 to 5.4 pmol/L).
Normal value ranges may vary slightly among different labs. Some labs use different measurements or may test different specimens. Talk to your provider about the meaning of your specific test results.
Most labs cannot run this test. Only very specialized labs can perform the assay correctly.
Serum co-peptin is now commonly used as a substitute for measuring ADH.
What Abnormal Results Mean
A higher-than-normal level may occur when too much ADH is released, either from the brain where it is made or from somewhere else in the body. This is called the syndrome of inappropriate ADH (SIADH).
Syndrome of inappropriate ADH (SIADH).
Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a condition in which the body makes too much antidiuretic hormone (ADH). ADH is ...
Read Article Now Book Mark ArticleThere are many reasons why your body may make too much ADH. Common situations when ADH is released into the blood when it should not be produced include:
- Medicines, such as certain seizure medicines, antidepressants, cancer medicines, opiates (less often), and heart, diabetes, and blood pressure medicines
- Surgery under general anesthesia
- Disorders of the brain, such as injury, infections, and stroke
- Brain surgery in the region of the hypothalamus
- Removal of a noncancerous (benign) pituitary tumor
- Tuberculosis
- Cancer (especially small cell cancer of the lung)
- Lung disease, such as pneumonia
-
Substance use disorder
Substance use disorder
Substance use disorder occurs when a person's use of alcohol or another substance (prescribed medicine or illegal drug) leads to health issues or pro...
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A higher-than-normal level of ADH may be found in people with heart failure, liver failure, or some kind of kidney disease.
A lower-than-normal level may indicate:
- Damage to the hypothalamus or pituitary gland
-
Central diabetes insipidus (a condition in which the kidneys are not able to conserve water)
Central diabetes insipidus
Central diabetes insipidus is a rare condition that involves extreme thirst and excessive urination.
Read Article Now Book Mark Article - Excessive thirst (polydipsia)
Polydipsia
Excessive thirst is an abnormal feeling of always needing to drink fluids.
Read Article Now Book Mark Article - Too much fluid in the blood vessels (volume overload)
Risks
There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another, and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
- Excessive bleeding
-
Fainting or feeling lightheaded
Fainting
Fainting is a brief loss of consciousness due to a drop in blood flow to the brain. The episode most often lasts less than a couple of minutes and y...
Read Article Now Book Mark Article - Multiple punctures to locate veins
-
Hematoma (blood accumulating under the skin)
Hematoma
A bruise is an area of skin discoloration. A bruise occurs when small blood vessels break and leak their contents into the soft tissue beneath the s...
Read Article Now Book Mark Article - Infection (a slight risk any time the skin is broken)
Reviewed By
Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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Verbalis JG. Posterior pituitary. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 206.
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