It is a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine paid.
A high level of antidiuretic hormone (ADH) causes the body to produce less urine. A low-level results in increased urine production.
Too little ADH in your blood can be caused by binge drinking or low blood serum osmolality, the concentration of particles in your blood.
A rare water metabolism disorder called central diabetes insipidus is sometimes the cause of ADH deficiency. This disease is characterized by a reduction in hormone production by the hypothalamus or by releasing antidiuretic hormone from the pituitary gland.
Common symptoms include polyuria (excessive urination) and polydipsia (extreme or exaggerated thirst).
People with central diabetes insipidus are often tired as their frequent urges to urinate interrupt their sleep. Your urine is clear, odorless, and has an abnormally low concentration of particles.
Central diabetes insipidus can lead to severe dehydration if left untreated. This disorder is not related to the more common diabetes, which affects the hormone insulin level in the blood.
When there is an elevated antidiuretic hormone level in the blood, the cause may be the syndrome of inappropriate ADH (SIADH). If the condition is acute, it may present nausea/vomiting and headaches. In severe cases, seizures and even coma can occur.
Increased ADH is associated with:
- Lung cancer.
- Pancreatic cancer.
- Bladder cancer.
- Brain cancer
- Systemic cancers that produce ADH.
- Guillain-Barré syndrome.
- Multiple sclerosis.
- Acute intermittent porphyria is a genetic disorder that affects the production of heme, an essential component of the blood.
- Cystic fibrosis.
Surgeries, dehydration, or brain trauma can also cause an excess of the hormone.
Nephrogenic diabetes insipidus is another sporadic disorder that can affect ADH levels. There is enough ADH in your blood if you have this condition, but your kidney cannot respond, diluting the urine. The signs and symptoms are similar to central diabetes insipidus.
Symptoms also include polyuria and polydipsia. Tests for this disorder will likely reveal normal or high ADH levels, which will help distinguish it from central diabetes insipidus.
Nephrogenic diabetes insipidus is not related to the more common diabetes mellitus, which affects the level of insulin in the blood.
What is an antidiuretic hormone (ADH) test?
The antidiuretic hormone test measures the amount of this hormone in the blood. This test is often combined with other tests to determine what is causing too much or too little of this hormone to be present in the blood.
Purpose of ADH level tests
The normal range for ADH is 1-5 picograms per milliliter (pg / mL). Several different problems can cause ADH levels that are too low or too high.
How the blood sample is taken
A healthcare provider will draw blood from your vein, usually in the lower elbow. During this process, the following occurs:
- The site is first cleaned with an antiseptic to kill germs.
- An elastic band is wrapped around your arm above the potential area of the vein where the blood will be drawn. This causes the vein to swell with blood.
- Your healthcare provider gently inserts a needle syringe into your vein. Blood is directed into the syringe tube until the tube is full. The needle is then removed.
- The elastic band is then released, and the injection site is covered with sterile gauze to stop the blood.
How to prepare for your blood test
Many medications and other substances can affect the levels of ADH in your blood. Before the test, your doctor may ask you to avoid:
- Clonidine is a blood pressure medicine.
- Haloperidol is a medicine used to treat psychotic and behavioral disorders.
Potential risks of having an ADH test
Uncommon risks of blood tests are:
- Excessive bleeding
- Infection at the puncture site.
Understand test results
Abnormally high levels of ADH may mean that you have:
- A brain injury or trauma.
- Un tumor is cerebral.
- A brain infection.
- Infection or tumor of the central nervous system.
- A lung infection
- Small cell carcinoma lung cancer.
- Fluid imbalance after surgery.
- Syndrome of inappropriate ADH (SIADH).
- Nephrogenic diabetes insipidus is very rare.
- Acute porphyria is very rare.
Abnormally low levels of ADH can mean:
- Pituitary damage
- Primary polydipsia.
- Central diabetes insipidus is rare.
Follow-up after the test
An ADH test alone is generally not enough to make a diagnosis. Your doctor will probably need to perform a combination of tests. Some tests that can be done with an ADH test include the following:
- An osmolality test is a blood or urine test that measures the concentration of dissolved particles in blood serum and urine.
- An electrolyte test is a blood test used to measure the number of electrolytes, usually sodium or potassium, in your body.
- A water deprivation test looks at how often you urinate if you stop drinking water for several hours.