Diabetes insipidus (die-uh-BEE-teze in-SIP-uh-dus) is an uncommon disorder that causes an imbalance of fluids in the body. This imbalance makes you very thirsty even if you've had something to drink. It also leads you to produce large amounts of urine.
While the terms "diabetes insipidus" and "diabetes mellitus" sound similar, they're not related. Diabetes mellitus — which can occur as type 1 or type 2 — is the more common form of diabetes.
There's no cure for diabetes insipidus. But treatments can relieve your thirst and decrease your urine output.
Signs and symptoms of diabetes insipidus include:
- Extreme thirst
- Producing large amounts of diluted urine
- Frequent need to get up to urinate during the night
- Preference for cold drinks
If your condition is serious, urine output can be as much as 20 quarts (about 19 liters) a day if you're drinking a lot of fluids. A healthy adult typically urinates an average of 1 or 2 quarts (about 1 to 2 liters) a day.
An infant or young child with diabetes insipidus may have the following signs and symptoms:
- Heavy, wet diapers
- Trouble sleeping
- Delayed growth
- Weight loss
When to see a doctor
See your doctor immediately if you notice excessive urination and extreme thirst.
Diabetes insipidus occurs when your body can't properly balance the body's fluid levels.
When your fluid regulation system is working properly, your kidneys help maintain this balance. The kidneys remove fluids from your bloodstream. This fluid waste is temporarily stored in your bladder as urine, until you urinate. The body can also rid itself of excess fluids through sweating, breathing or diarrhea.
A hormone called anti-diuretic hormone (ADH), or vasopressin, helps control how fast or slow fluids are excreted. ADH is made in a part of the brain called the hypothalamus and stored in the pituitary gland, a small gland found in the base of the brain.
Nephrogenic diabetes insipidus that's present at or shortly after birth usually has an inherited (genetic) cause that permanently changes the kidneys' ability to concentrate the urine. Nephrogenic diabetes insipidus usually affects males, though women can pass the gene on to their children.
Diabetes insipidus may lead to dehydration. Dehydration can cause:
- Dry mouth
- Changes in skin elasticity
Diabetes insipidus can cause an imbalance in electrolytes — minerals in your blood, such as sodium and potassium, that maintain the fluid balance in your body. Symptoms of an electrolyte imbalance may include:
- Loss of appetite
- Muscle cramps
Some of the tests doctors use to diagnose diabetes insipidus include:
Water deprivation test. While being monitored by a doctor and health care team, you'll be asked to stop drinking fluids for several hours. To prevent dehydration while fluids are restricted, ADH allows your kidneys to decrease the amount of fluid lost in the urine.
While fluids are being withheld, your doctor will measure changes in your body weight, urine output, and the concentration of your urine and blood. Your doctor may also measure blood levels of ADH or give you synthetic ADH during this test. This will determine if your body is producing enough ADH and if your kidneys can respond as expected to ADH.
- Magnetic resonance imaging (MRI). An MRI can look for abnormalities in or near the pituitary gland. This test is noninvasive. It uses a powerful magnetic field and radio waves to construct detailed pictures of brain tissues.
- Genetic screening. If others in your family have had problems with excess urination, your doctor may suggest genetic screening.
Treatment options for the most common types of diabetes insipidus include:
Central diabetes insipidus. If you have mild diabetes insipidus, you may only need to increase your water intake. If the condition is caused by an abnormality in the pituitary gland or hypothalamus (such as a tumor), your doctor will first treat the abnormality.
Typically, this form is treated with a man-made hormone called desmopressin (DDAVP, Minirin, others). This medication replaces the missing anti-diuretic hormone (ADH) and decreases urination. You can take desmopressin as a nasal spray, as oral tablets or by injection.
Most people still make some ADH, though the amount can vary day to day. So, the amount of desmopressin you need also may vary. Taking more desmopressin than you need can cause water retention and potentially serious low-sodium levels in the blood.
Other medications may also be prescribed, such as indomethacin (Indocin, Tivorbex) and chlorpropamide. These drugs can make ADH more available in the body.
Nephrogenic diabetes insipidus. Since the kidneys don't properly respond to ADH in this form of diabetes insipidus, desmopressin won't help. Instead, your doctor may prescribe a low-salt diet to help reduce the amount of urine your kidneys make. You'll also need to drink enough water to avoid dehydration.
Treatment with the drug hydrochlorothiazide (Microzide) may improve your symptoms. Although hydrochlorothiazide is a type of drug that usually increases urine output (diuretic), in some people it can reduce urine output for people with nephrogenic diabetes insipidus.
If your symptoms are due to medications you're taking, stopping these medicines may help. However, don't stop taking any medication without first talking to your doctor.
- Gestational diabetes insipidus. Treatment for most people with gestational diabetes insipidus is with the synthetic hormone desmopressin.
- Primary polydipsia. There is no specific treatment for this form of diabetes insipidus, other than decreasing fluid intake. If the condition is related to a mental illness, treating the mental illness may relieve the diabetes insipidus symptoms.
If you have diabetes insipidus:
- Prevent dehydration. As long as you take your medication and have access to water when the medication's effects wear off, you'll prevent serious problems. Plan ahead by carrying water with you wherever you go, and keep a supply of medication in your travel bag, at work or at school.
- Wear a medical alert bracelet or carry a medical alert card in your wallet. If you have a medical emergency, a health care professional will recognize immediately your need for special treatment.
You're likely to first see your primary care doctor. However, in some cases when you call to set up an appointment you may be referred to a specialist called an endocrinologist.
Here's some information to help you get ready for your appointment.
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance. Your doctor may ask you to stop drinking water the night before, but do so only if your doctor asks you to.
- Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment. Be prepared to answer specific questions about how often you urinate and how much water you drink each day.
- Write down key personal information, including any major stresses or recent life changes.
- Make a list of your key medical information, including recent surgical procedures, the names of all medications you're taking and any other conditions for which you've recently been treated. Your doctor will also want to know about any recent injuries to your head.
- Take a family member or friend along, if possible. Sometimes it can be difficult to remember all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
- Write down questions to ask your doctor.
For diabetes insipidus, some basic questions to ask your doctor include:
- What's the most likely cause of my symptoms?
- What kinds of tests do I need?
- Is my condition likely temporary or will I always have it?
- What treatments are available and which do you recommend for me?
- How will you monitor whether my treatment is working?
- Will I need to make any changes to my diet or lifestyle?
- Will I still need to drink a lot of water if I'm taking medications?
- I have other health conditions. How can I best manage these conditions together?
- Are there any dietary restrictions I need to follow?
- Are there brochures or other printed material I can take home or websites you recommend?
What to expect from your doctor
Your doctor is likely to ask you a number of questions, including:
- When did you begin experiencing symptoms?
- How much more are you urinating than usual?
- How much water do you drink each day?
- Do you get up at night to urinate and drink water?
- Are you pregnant?
- Are you being treated or have you recently been treated for other medical conditions?
- Have you had any recent head injuries or have you had neurosurgery?
- Has anyone in your family been diagnosed with diabetes insipidus?
- Does anything seem to improve your symptoms?
- What, if anything, appears to worsen your symptoms?
What you can do in the meantime
While you're waiting for your appointment, drink until your thirst is relieved, as often as necessary. Avoid activities that might cause dehydration, such as physical exertion or spending time in the heat.