What Is Diabetes Insipidus?
Diabetes insipidus is a rare condition that causes your body to make a lot of urine that is "insipid," or colorless and odorless. Most people pee out 1 to 2 quarts of urine a day. People with diabetes insipidus can pass between 3 and 20 quarts a day.
Diabetes Insipidus vs. Diabetes Mellitus
Diabetes insipidus is a different disease than diabetes mellitus. Despite the similar names, the only things these two have in common is that they make you thirsty and make you pee a lot.
If you have diabetes insipidus, the hormones that help your body balance liquids don’t work. Only one in every 25,000 people gets this condition.
With diabetes (also called diabetes mellitus), your body can’t use energy from food like it should. It’s far more common. Around 100 million Americans have type 1 or type 2 diabetes.
Symptoms of Diabetes Insipidus
You might notice:
What Causes Diabetes Insipidus?
Your body makes a substance called vasopressin. It’s made in a part of your brain called the hypothalamus and stored in your pituitary gland. It tells your kidneys to hold on to water, which makes your urine more concentrated. (Vasopressin is also called antidiuretic hormone, or ADH.)
When you’re thirsty or slightly dehydrated, vasopressin levels rise. Your kidneys reabsorb more water and put out concentrated urine. If you’ve had plenty to drink, vasopressin levels fall and what comes out is clear and diluted.
In either form, the result is the same. Your kidneys can't retain water, so even if you’re dehydrated, they'll put out a lot of pale urine.
Types of Diabetes Insipidus
- Central diabetes insipidus. You get this when damage to the hypothalamus or pituitary gland disrupts your body's ability to make or release vasopressin. Your kidneys remove too much fluid from your body, and you pee more. Damage to the hypothalamus or pituitary gland can result from:
Central diabetes insipidus can also happen if your parents pass down to you a defect in the gene that makes vasopressin, though this cause is rare. In some cases, doctors can’t find the cause.
- Nephrogenic diabetes insipidus. You get this when your kidneys don’t respond to vasopressin and take too much fluid from your bloodstream. We don’t always know what brings on nephrogenic diabetes insipidus, but some causes include:
Dipsogenic diabetes insipidus. This type happens when your body has problems controlling thirst. When you drink, the liquid lowers the amount of vasopressin your body creates while making you pee more. Causes include damage to the hypothalamus or pituitary glands from:
- A tumor
- Head injury
- A tumor
Some medications or mental health problems could make you more likely to get dipsogenic diabetes insipidus.
- Gestational diabetes insipidus. You can only get this type during pregnancy. Sometimes the placenta -- the organ that gives oxygen and nutrients to your baby -- creates an enzyme that breaks down the mother's vasopressin. And some pregnant women make more prostaglandin, a hormone-like chemical that makes their kidneys less sensitive to vasopressin. Most cases of gestational diabetes insipidus are mild and don’t cause noticeable symptoms. The condition usually goes away after birth, but it might come back during another pregnancy.
How Is Diabetes Insipidus Diagnosed?
If you have this condition, you’ll probably wind up at the doctor for help with your thirst and constant need for a bathroom.
To diagnose you, first the doctor will do a physical exam. Then they’ll ask questions about your health history, including your family’s health. You might get a series of tests that include:
- Urinalysis. You’ll give a sample of your pee, and the doctor will send it to a lab to see if it’s dilute or concentrated. They can also check for glucose, which can help the doctor decide if you have diabetes insipidus or diabetes. You might even collect your pee over a 24-hour period to see how much you’re putting out.
- Blood test. This will measure the amount of electrolytes and glucose in your blood. This lets the doctor know you have diabetes or diabetes insipidus. It may even help them figure out which type.
Fluid deprivation test. This measures the changes in your body weight, blood sodium, and urine concentration after you don’t drink anything for a while. If your blood sodium or concentration levels rise way above normal and your urine concentration is low, you probably have diabetes insipidus.There are two types:
- Short-form fluid deprivation test. You stop drinking for a short period. You collect a sample and tack it back to the doctor, who sends it to the lab.
- Formal fluid deprivation test. You’ll have this done in a hospital so doctors can make sure you don’t get dehydrated. You’ll be weighed and have a sample taken every hour or two until:
- Your blood pressure drops too low or you have a rapid heartbeat when you stand
- You lose 5% or more of your starting body weight
- Your urine concentration goes up a little bit over 2 or 3 measurements
- Magnetic resonance imaging. This test takes detailed pictures your internal organs and soft tissues. The doctor uses it to see if you have a problem with your hypothalamus or pituitary gland.
- Genetic screening. Your doctor may suggest this type of test if your family members have had problems with making too much urine.
Complications of Diabetes Insipidus
If you don’t keep your diabetes insipidus under control, you might be more likely to get complications like:
- Dehydration. Diabetes insipidus makes it hard for your body to hold on to water. It’s easy to get dehydrated. If you have diabetes insipidus, watch out for signs like:
- Electrolyte Imbalance. Electrolytes are minerals in your body with a tiny electric charge. When you lose too much water, your electrolyte levels can go up. When this happens, you might notice:
- Less sleep. Diabetes insipidus can lead to nocturia, a medical name for waking up in the night to pee. The result: a less restful night.
Diabetes Insipidus Treatment
First, the doctor will tell you to drink plenty of fluids. That will replace the constant loss of water.
- Central diabetes insipidus. You’ll take medications like desmopressin (DDAVP) or vasopressin (Pitressin). It usually comes as a nasal spray. There are also treatments to help these drugs work better.
- Nephrogenic diabetes insipidus can be harder to treat. If it’s caused by a drug, stopping the medicine helps. Other medicines may improve the symptoms. These include indomethacin (Indocin) and diuretics like amiloride (Moduretic 5-50) or hydrochlorothiazide (Microzide). Though diuretics typically make you pee more, in this case they help you make less urine. Sometimes it goes away if you treat the cause.
- Dipsogenic diabetes insipidus. There isn’t an effective treatment for this condition. Suck on ice chips or sour candy to help moisten your mouth, boost saliva flow, and lower your desire to drink. If you wake up to pee several times a night, a small dose of desmopressin at bedtime might help.
- Gestational diabetes insipidus. You can take desmopressin while you’re pregnant. Your problems should go away after you have the baby.
How Serious Is It?
Diabetes insipidus doesn’t cause kidney failure or lead to dialysis. Your kidneys still do their main job, which is to filter your blood.
But you will be more prone to dehydration. Make sure you always have something to drink close by, especially when it’s hot or when you exercise.