Despite the name, diabetes insipidus is not related to type 1 or type 2 diabetes (diabetes mellitus). Diabetes insipidus is a hormone disorder that occurs when the body doesn't produce enough antidiuretic hormone (ADH) or doesn't use the hormone effectively.
The symptoms of diabetes insipidus include extreme thirst and excessive urination. In a normal adult, the average amount of urine is 1.6 to 2.6 quarts per day. People who have diabetes insipidus may urinate up to 16 quarts a day. They may also have to get up frequently during the night to urinate, and may even wet the bed.
Diabetes insipidus has several causes. In some people, a part of the brain (called the hypothalamus) doesn't make enough antidiuretic hormone (ADH). ADH helps your body balance water in the urine and blood. In other cases, the pituitary gland (which is responsible for releasing the ADH into the body) doesn't release enough of the hormone. Damage to either the hypothalamus or the pituitary gland can cause diabetes insipidus. This can occur after a head injury, during brain surgery or when a tumor grows on the glands.
Abnormalities in the kidneys can also cause diabetes insipidus. If the kidneys are abnormal, it can affect the way they process ADH.
Diabetes insipidus can be caused by some medicines, such as lithium.
About 30% of the time, doctors can't find the cause.
To check for diabetes insipidus, your doctor may order a urine test. This will show how much water is in your urine, and can rule out type 1 or type 2 diabetes (if you have type 1 or type 2 diabetes, there will be excess sugar in your urine). Your doctor might do a blood test to check for high sodium levels, which is another indication of diabetes insipidus.
Your doctor may also order a water deprivation test. During this test, you aren't allowed to drink any liquids. The staff will weigh you, check your urine and blood every hour for several hours. If the results of the test show that you have diabetes insipidus, you will probably also have pictures taken of your brain with an MRI (magnetic resonance image) scan. The scans can show problems or tumors in the brain that could be causing your diabetes insipidus.
If your symptoms are mild, you might not need treatment. However, your doctor will want to check on you more often. Also, you should make sure you always have something to drink, so your body doesn't get dehydrated.
For more severe cases of diabetes insipidus, medicine is available to help the body produce or more effectively use ADH. One medicine called desmopressin is a synthetic form of ADH and comes in pill form, as an injection (shot) or as a nasal spray. If you take desmopressin, you shouldn't drink too much, or your body will get overloaded with fluids. Too much fluid in your body and make you feel sick, weak or dizzy.
If tumors or abnormal growths on your hypothalamus or pituitary gland are causing your diabetes insipidus, your doctor may suggest surgery to remove the growths.
If your diabetes insipidus is caused by kidney problems, your doctor may recommend that you reduce salt in your diet and to drink enough water to avoid dehydration. Medicines like hydrochlorothiazide (a water pill) may also help. Water pills help your body balance salt and water.
If a medicine is causing diabetes insipidus, your doctor may prescribe another medicine that doesn't cause excessive thirst and urination.
Talk to your doctor about which option is right for you.
Written by familydoctor.org editorial staff