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Alternative names
Arginine vasopressin; Antidiuretic hormone; AVP; VasopressinDefinition Return to top
ADH is a test that measures the amount of ADH in serum. ADH is a hormone found in the body. It may also be given as a medication.How the test is performed Return to top
Adult or child:Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic. An elastic band is placed around the upper arm to apply pressure and cause the vein to swell with blood.
A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
In infants or young children:
The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. A bandage may be applied to the puncture site if there is any bleeding.
How to prepare for the test Return to top
Consult your health care provider about your medications before the test. Many medications, including nicotine, insulin, diuretics, lithium, morphine, alcohol, steroids, haloperidol, and clonidine can affect ADH measurements.How the test will feel Return to top
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.Why the test is performed Return to top
This test is performed if a disorder that affects the ADH level is suspected.
ADH is a hormone stored in the posterior pituitary gland in the brain. It is the primary regulator of body water. ADH acts on the kidneys to increase total body water. This decreases the plasma concentration, increasing blood volume and increasing blood pressure.
The release of ADH is controlled by cells, called osmoreceptors and baroreceptors. Osmoreceptors are specialized areas in the hypothalamus (an area in the brain). These cells sense the concentration of particles in the blood. When the concentration is high, the pituitary releases more ADH. This stimulates retention of water to dilute the body fluids. When the concentration is low, the pituitary releases less ADH. Baroreceptors are specialized areas in the heart that sense blood volume and blood pressure. The heart signals the pituitary to release more ADH when blood volume or blood pressure are low and less when they are high.
In certain diseases, the normal release of ADH is altered, and the serum level of ADH must be tested to determine the cause.
Normal Values Return to top
Values of 0 to 4.7 pg/mL are normal. Normal value ranges may vary slightly among different laboratories.What abnormal results mean Return to top
Greater-than normal-levels may indicate:What the risks are Return to top
Special considerations Return to top
There are none.
Update Date: 2/2/2004 Updated by: Tarun Jain, M.D., Endocrinology & Infertility Division, Brigham and Women's Hospital, Boston, MA. Review provided by VeriMed Healthcare Network.
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Page last updated: 28 October 2004 |