Antidiuretic hormone blood test
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 control the amount of water excreted in the urine.
Hypothalamus
The hypothalamus is an area of the brain that produces hormones that control:Body temperatureHeart rateHungerMoodRelease of hormones from many glands...
Read Article Now Book Mark ArticleADH blood test is ordered when your provider suspects you have a disorder that affects your 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 laboratories. Some labs use different measurements or may test different specimens. Talk to your provider about the meaning of your specific test results.
Most laboratories cannot run this test. Only very specialized laboratories 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 ArticleCauses of SIADH include:
- Brain injury or trauma
- Brain tumors
- Fluid imbalance after surgery
- Infection in the brain or the tissue that surrounds the brain
Infection in the brain
Encephalitis is irritation and swelling (inflammation) of the brain, most often due to infections.
Read Article Now Book Mark ArticleThe tissue that surrounds the brain
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.
Read Article Now Book Mark Article - Infection in the lungs
Infection in the lungs
Pneumonia is a breathing (respiratory) condition in which there is an infection of the lung. This article covers community-acquired pneumonia (CAP). ...
Read Article Now Book Mark Article - Certain medicines, such as some seizure medicines, pain medicines, and antidepressants
- Small cell carcinoma lung cancer
Small cell carcinoma lung cancer
Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It spreads much more quickly than non-small cell lung cancer. There are two typ...
Read Article Now Book Mark Article - Stroke
Stroke
A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack. " If blood flow is cut off for longer th...
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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.
Frasier LL, Keating JJ, Shiroff AM. Endocrine responses in critically ill and trauma patients. In: Shifrin AL, ed. Endocrine Emergencies. Philadelphia, PA: Elsevier; 2022:chap 25.
Guber HA, Oprea M, Russell YX. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. St Louis, MO: Elsevier; 2022:chap 25.
Oh MS, Briefel G, Pincus MR. Evaluation of renal function, water, electrolytes, and acid-base balance. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. St Louis, MO: Elsevier; 2022:chap 15.