Also Known As
Vasopressin
AVP
Formal Name
Antidiuretic Hormone; Arginine Vasopressin
This article was last reviewed on
This article waslast modified on December 4, 2017.
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

Sample Required?

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.

You may be able to find your test results on your laboratory's website or patient portal. However, you are currently at Lab Tests Online. You may have been directed here by your lab's website in order to provide you with background information about the test(s) you had performed. You will need to return to your lab's website or portal, or contact your healthcare practitioner in order to obtain your test results.

Lab Tests Online is an award-winning patient education website offering information on laboratory tests. The content on the site, which has been reviewed by laboratory scientists and other medical professionals, provides general explanations of what results might mean for each test listed on the site, such as what a high or low value might suggest to your healthcare practitioner about your health or medical condition.

The reference ranges for your tests can be found on your laboratory report. They are typically found to the right of your results.

If you do not have your lab report, consult your healthcare provider or the laboratory that performed the test(s) to obtain the reference range.

Laboratory test results are not meaningful by themselves. Their meaning comes from comparison to reference ranges. Reference ranges are the values expected for a healthy person. They are sometimes called "normal" values. By comparing your test results with reference values, you and your healthcare provider can see if any of your test results fall outside the range of expected values. Values that are outside expected ranges can provide clues to help identify possible conditions or diseases.

While accuracy of laboratory testing has significantly evolved over the past few decades, some lab-to-lab variability can occur due to differences in testing equipment, chemical reagents, and techniques. This is a reason why so few reference ranges are provided on this site. It is important to know that you must use the range supplied by the laboratory that performed your test to evaluate whether your results are "within normal limits."

For more information, please read the article Reference Ranges and What They Mean.

What is being tested?

Antidiuretic hormone (ADH), also called arginine vasopressin (AVP), is a hormone that helps regulate water balance in the body by controlling the amount of water the kidneys reabsorb while they are filtering wastes out of the blood. This test measures the amount of ADH in the blood.

ADH is produced by the hypothalamus in the brain and stored in the posterior pituitary gland at the base of the brain. ADH is normally released by the pituitary in response to sensors that detect an increase in blood osmolality (number of dissolved particles in the blood) or decrease in blood volume. The kidneys respond to ADH by conserving water and producing urine that is more concentrated. The retained water dilutes the blood, lowers its osmolality, and increases blood volume and pressure. If this is not sufficient to restore the water balance, then thirst is also stimulated so that the affected person will drink more water.

There are a variety of disorders, conditions, and medications that can affect either the amount of ADH released or the kidneys' response to it. ADH deficiency and excess can cause acute and chronic symptoms that, in rare cases, may become life-threatening.

If there is too little ADH or the kidneys do not respond to ADH, then too much water is lost through the kidneys, the urine produced is more dilute than normal, and the blood becomes more concentrated. This can cause excessive thirst, frequent urination, dehydration, and – if not enough water is ingested to replace what is being lost – high blood sodium (hypernatremia).

If there is too much ADH, then water is retained, blood volume increases, and the person may experience nausea, headaches, disorientation, lethargy, and low blood sodium (hyponatremia).

The ADH test is not widely used to diagnose these conditions. Often, a diagnosis is made on the basis of clinical history and other laboratory tests, such as urine and blood osmolality and electrolytes.

ADH deficiency is called diabetes insipidus. There are two types of this disorder: central and nephrogenic.

  • Central diabetes insipidus is associated with a lack of ADH production by the hypothalamus or release from the pituitary and may be due to a variety of causes, including an inherited genetic defect, head trauma, a brain tumor, or due to an infection that causes encephalitis or meningitis.
  • Nephrogenic diabetes insipidus originates in the kidney and is associated with a lack of response to ADH, causing an inability to concentrate urine. It may be inherited or caused by a variety of kidney diseases.

Both types of diabetes insipidus lead to the excretion of large quantities of dilute urine.

Increased levels of ADH are often seen with "syndromes of inappropriate antidiuretic hormone" (SIADH) secretion. SIADH is characterized by inappropriate (that is, not due to high blood osmolality or low blood volume) production of too much ADH, resulting in water retention, low blood sodium, and decreased blood osmolality. It may be due to a wide number of diseases and conditions that either stimulate excessive ADH production and release or that prevent its suppression. SIADH may also be seen with cancers that produce ADH or ADH-like substances independent of the hypothalamus and pituitary glands. Regardless of the cause or source, excessive ADH causes low blood sodium and osmolality because water is retained and blood volume is increased.

How is the sample collected for testing?

A blood sample is obtained by inserting a needle into a vein in the arm.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is 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.

Accordion Title
Common Questions
  • How is it used?

    The antidiuretic hormone (ADH) test is used to help detect, diagnose, and determine the cause of antidiuretic hormone deficiencies and excesses. However, this test is not widely used; diagnoses of these conditions are often based on clinical history and other laboratory tests, such as blood and urine osmolality as well as electrolytes.

    Antidiuretic hormone, also called arginine vasopressin (AVP), is a hormone produced by the hypothalamus in the brain and stored in the posterior pituitary gland at the base of the brain. ADH helps regulate water balance in the body. A variety of disorders, conditions, and medications can affect either the amount of ADH released or the kidneys' response to it.

    ADH deficiency is often seen with one of two types of diabetes insipidus. Central diabetes insipidus is a decrease in the production of ADH by the hypothalamus or in the release of ADH from the pituitary while nephrogenic diabetes insipidus is characterized by a decrease in the kidney's response to ADH. Both types of diabetes insipidus lead to the excretion of large quantities of dilute urine.

    A water deprivation ADH stimulation test is sometimes used to distinguish between these types. It involves fluid restriction, an ADH test, and the administration of ADH (vasopressin). Several blood and urine osmolality measurements are performed at timed intervals before and after vasopressin is given in order to monitor the body's response to fluid restriction and then to the drug. This procedure must be performed under close medical supervision as it can sometimes lead to severe dehydration and can pose a risk to some people with underlying diseases.

    An increased level of ADH is often seen with "syndromes of inappropriate ADH" secretion (SIADH). Testing for SIADH may include blood and urine osmolality, sodium, potassium, and chloride tests, and sometimes an ADH measurement. A water loading ADH suppression test is sometimes performed. With this procedure, a fasting person is given specific quantities of water and then the amount of urine produced and the changes in urine and blood osmolality are monitored over time. An ADH test is also performed. This procedure must also be performed under medical supervision as it can be risky in those with kidney disease and can sometimes result in severe low blood sodium (hyponatremia).

    Other testing may be performed to help distinguish SIADH from other disorders that can cause edema, low blood sodium, and/or decreased urine production, such as congestive heart failure, liver disease, kidney disease, and thyroid disease.

  • When is it ordered?

    An ADH test may be ordered by itself, along with other tests, or as part of a water deprivation or water loading procedure when excess or deficient ADH production and secretion is suspected. It may be ordered when a person has low blood sodium without an identifiable cause and/or has symptoms associated with SIADH. If SIADH develops gradually, there may be no symptoms, but if the condition is acute, the signs and symptoms are usually those associated with water intoxication and may include:

    • Headache
    • Nausea, vomiting
    • Confusion
    • In severe cases, coma and convulsions

    An ADH test may be ordered when a person has excessive thirst and frequent urination and the health practitioner suspects diabetes insipidus.

  • What does the test result mean?

    ADH test results alone are not diagnostic of a specific condition. The results are usually evaluated in conjunction with a person's medical history, physical examination, and results of other tests. Excesses and deficiencies of ADH may be temporary or persistent, acute or chronic, and may be due to an underlying disease, an infection, an inherited condition, or due to brain surgery or trauma.

    Increased ADH levels are often associated with SIADH, which may be due to a variety of cancers, including leukemia, lymphoma, and cancers of the lung, pancreas, bladder, and brain. Levels of ADH may be greatly increased with such cancers. Moderate increases in ADH may be seen with nervous system disorders such as Guillain-Barré syndrome, multiple sclerosis, epilepsy, and acute intermittent porphyria, with pulmonary disorders such as cystic fibrosis, emphysema, and tuberculosis, and in those with HIV/AIDS. The ADH test may sometimes be ordered to help investigate low blood sodium and its associated symptoms, and to identify SIADH, but it is not generally ordered to diagnose or monitor any of the diseases or conditions that may cause it.

    A low ADH may be seen with central diabetes insipidus, excessive water drinking, and with low serum osmolality. An increased ADH may be seen with nephrogenic diabetes insipidus, with dehydration, trauma, and surgery.

    With ADH suppression or stimulation tests, a health practitioner is looking for appropriate levels of ADH, osmolality, and kidney water retention responses.

    • A water loading ADH suppression test may be used to help diagnose SIADH. With this test, those with SIADH typically have decreased blood sodium and osmolality. They do not produce as much urine as expected, urine osmolality is high relative to serum osmolality, and the ADH concentration is in excess of what would be appropriate and does not decrease appropriately with water loading.
    • A water deprivation ADH stimulation test may be used to differentiate between the two types of diabetes insipidus.
      • Central diabetes insipidus is characterized by abnormally low production of ADH and the inability to concentrate urine that is reflected as an increase in urine osmolality after ADH administration but not an increase due to water deprivation alone.
      • Nephrogenic diabetes insipidus is the kidney's inability to respond to ADH that is reflected as no change in urine osmolality before or after ADH administration and high blood ADH.
  • Is there anything else I should know?

    In general, the ability to concentrate urine decreases with age.

    ADH secretion increases when a person is standing, at night, and with pain, stress and exercise. Secretion decreases with hypertension and when someone is lying down.

    Many drugs can affect ADH levels. They include:

  • Should everyone have an ADH test?
    No, for most people, ADH is appropriately produced and utilized by the body to maintain water balance. The ADH test is not used as a general screening test and most people will never have one done.
  • Can the ADH test be performed in my doctor's office?
    Your blood may be collected in the doctor's office, but ADH testing requires specialized equipment. The test is not offered by every laboratory and may need to be sent to a reference laboratory. If you have a water deprivation or water loading test, it will be performed under medical supervision.
  • How is diabetes insipidus different than diabetes mellitus?

    Diabetes mellitus, usually referred to as diabetes, is related to either decreased insulin production or insulin resistance and causes an increase in blood glucose. Diabetes insipidus is not related to insulin or glucose. The ancient Greeks, in naming the diseases, thought that both conditions were similar because persons with them had increased thirst and frequent urination. They were different in that, in one, the urine was sweet (diabetes mellitus) while in the other, is was not (diabetes insipidus).

  • Can diabetes insipidus be treated?

    Yes, a synthetic form of ADH can be given as a replacement to those with central diabetes insipidus. Those with nephrogenic diabetes insipidus are encouraged to drink adequate amounts of water to replace what is being lost in their urine and should talk to their health care provider about possible adjustments to their diet.

View Sources

Sources Used in Current Review

Khardori, R. et. al. (Updated 2013 March 8) Diabetes Insipidus. Medscape Reference [On-line information]. Available online at http://emedicine.medscape.com/article/117648-overview through http://emedicine.medscape.com. Accessed November 2013.

(© 1995–2013). Arginine Vasopressin, Plasma. Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at http://www.mayomedicallaboratories.com/test-catalog/Overview/80344 through http://www.mayomedicallaboratories.com. Accessed November 2013.

Rennert, N. (Updated 2011 December 11). ADH. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003702.htm through http://www.nlm.nih.gov. Accessed November 2013.

Pagana, K. D. & Pagana, T. J. (© 2011). Mosby's Diagnostic and Laboratory Test Reference 10th Edition: Mosby, Inc., Saint Louis, MO. Pp 78-80.

Clarke, W., Editor (© 2011). Contemporary Practice in Clinical Chemistry 2nd Edition: AACC Press, Washington, DC. Pp 424-426, 428.

McPherson, R. and Pincus, M. (© 2011). Henry's Clinical Diagnosis and Management by Laboratory Methods 22nd Edition: Elsevier Saunders, Philadelphia, PA. Pp 183-187, 370-373.

Sources Used in Previous Reviews

Pagana, K. D. & Pagana, T. J. (© 2007). Mosby's Diagnostic and Laboratory Test Reference 8th Edition: Mosby, Inc., Saint Louis, MO. Pp 76-78.

Clarke, W. and Dufour, D. R., Editors (© 2006). Contemporary Practice in Clinical Chemistry: AACC Press, Washington, DC. Pp 133.

Eckman, A. (Updated 2009 October 14). ADH. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003702.htm through http://www.nlm.nih.gov. Accessed February 2010.

Patel, P. (Updated 2009 October 14). Diabetes insipidus. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000377.htm through http://www.nlm.nih.gov. Accessed February 2010.

Ferry, R. et. al. (Updated 2009 October 22). Syndrome of Inappropriate Antidiuretic Hormone Secretion. Emedicine [On-line information]. Available online at http://emedicine.medscape.com/article/924829-overview through http://emedicine.medscape.com. Accessed February 2010.

Deshmukh, S. and Thomas, C. (Updated 2009 May 28). Syndrome of Inappropriate Secretion of Antidiuretic Hormone. eMedicine [On-line information]. Available online at http://emedicine.medscape.com/article/246650-overview through http://emedicine.medscape.com. Accessed February 2010.

Resnick, B. (2009 December 28). What Causes Hyponatremia in an Elderly Patient? Medscape Today [On-line information]. Available online at http://www.medscape.com/viewarticle/714108 through http://www.medscape.com. Accessed February 2010.

Lewis, J. (Revised 2009 May). Water and Sodium Balance Merck Manual for Healthcare Professionals [On-line information]. Available online at http://www.merck.com/mmpe/sec12/ch156/ch156b.html?qt=ADH&alt=sh through http://www.merck.com. Accessed February 2010.

Lewis, J. (Revised 2009 May). Hyponatremia. Merck Manual for Healthcare Professionals [On-line information]. Available online at http://www.merck.com/mmpe/sec12/ch156/ch156d.html through http://www.merck.com. Accessed February 2010.

Mayo Clinic staff (2009 July 14) Hyponatremia. MayoClinic.com [On-line information]. Available online at http://www.mayoclinic.com/health/hyponatremia/DS00974 through http://www.mayoclinic.com. Accessed February 2010.

(Revised 2009 February 17). Detailed Guide: Pituitary Tumor, What Are Pituitary Tumors? American Cancer Society [On-line information]. Available online at http://www.cancer.org/docroot/CRI/content/CRI_2_4_1x_What_Are_Pituitary_Tumors_61.asp?sitearea= through http://www.cancer.org. Accessed February 2010.

Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson JL eds, (2005). Harrison's Principles of Internal Medicine, 16th Edition, McGraw Hill, Pp 2097-2102.

Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Burtis CA, Ashwood ER, Bruns DE, eds. St. Louis: Elsevier Saunders; 2006, Pp 1992-1996.

Ask a Laboratory Scientist

This form enables you to ask specific questions about lab tests. Your questions will be answered by a laboratory scientist as part of a voluntary service provided by one of our partners, American Society for Clinical Laboratory Science.

Disclaimer
Thank you for using the Consumer Information Response Service ("the Service") to inquire about the meaning of your lab test results.  The Service is provided free of charge by the American Society for Clinical Laboratory Science, which is one of many laboratory organizations that supports Lab Tests Online.
Please note that information provided through this free Service is not intended to be medical advice and should not be relied on as such. Although the laboratory provides the largest single source of objective, scientific data on patient status, it is only one part of a complex biological picture of health or disease. As professional clinical laboratory scientists, our goal is to assist you in understanding the purpose of laboratory tests and the general meaning of your laboratory results. It is important that you communicate with your physician so that together you can integrate the pertinent information, such as age, ethnicity, health history, signs and symptoms, laboratory and other procedures (radiology, endoscopy, etc.), to determine your health status. The information provided through this Service is not intended to substitute for such consultations with your physician nor specific medical advice to your health condition.
By submitting your question to this Service, you agree to waive, release, and hold harmless the American Society for Clinical Laboratory Science and its affiliates or their past or present officers, directors, employees, agents, and Service volunteers (collectively referred to as "ASCLS") and the American Association  for Clinical Chemistry and its affiliates or their past or present officers, directors, employees, agents, and Service volunteers (collectively referred to as "AACC") from any legal claims, rights, or causes of action you may have in connection with the responses provided to the questions that you submit to the Service.
AACC, ASCLS and its Service volunteers disclaim any liability arising out of your use of this Service or for any adverse outcome from your use of the information provided by this Service for any reason, including but not limited to any misunderstanding or misinterpretation of the information provided through this Service.