Antidiuretic Hormone: What is it? Deficiency, Excess, Test, Preparation and Potential Risks

It is a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine produced.

A high level of antidiuretic hormone (ADH) causes the body to produce less urine. A low level results in increased urine production.

ADH deficiency

Too little ADH in your blood can be caused by binge drinking or low blood serum osmolality, which is 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 the release of antidiuretic hormone from the pituitary gland.

Common symptoms include: polyura (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 level of the hormone insulin in the blood.

ADH excess

When there is an elevated level of antidiuretic hormone 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 very serious cases, seizures and even coma can occur.

Increased ADH is associated with:

  • Leukemia.
  • Lymphoma
  • Lung cancer.
  • Pancreatic cancer.
  • Bladder cancer.
  • Brain cancer
  • Systemic cancers that produce ADH.
  • Guillain-Barré syndrome.
  • Multiple sclerosis.
  • Epilepsy.
  • Acute intermittent porphyria, which is a genetic disorder that affects the production of heme, an important component of the blood.
  • Cystic fibrosis.
  • Emphysema.
  • Tuberculosis.
  • VIH.
  • PAGE.

Surgeries, dehydration, or brain trauma can also cause an excess of the hormone.

Nephrogenic diabetes insipidus is another very rare disorder that can affect ADH levels. If you have this condition, there is enough ADH in your blood, but your kidney cannot respond, resulting in very dilute urine. The signs and symptoms are similar to central diabetes insipidus.

Symptoms also include polyura 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 find out 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). ADH levels that are too low or too high can be caused by a number of different problems .

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:

  1. The site is first cleaned with an antiseptic to kill germs.
  2. 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.
  3. 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.
  4. 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:

  • Alcohol.
  • Clonidine, which is a blood pressure medicine.
  • Diuretics
  • Haloperidol, which is a medicine used to treat psychotic and behavioral disorders.
  • Insulin.
  • Lithium.
  • Morphine.
  • Nicotine.
  • Steroids

Potential risks of having an ADH test

Uncommon risks of blood tests are:

  • Excessive bleeding
  • Fainting.
  • Daze.
  • Hematoma.
  • 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 cerebral.
  • A brain infection.
  • An 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, which is very rare.
  • Acute porphyria, which is very rare.

Abnormally low levels of ADH can mean:

  • Pituitary damage
  • Primary polydipsia.
  • Central diabetes insipidus, which 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 amount 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.