Published: 18 Jun 2025

ICD9: 253.5      ICD10: E23.2      ICD11: 5A61.5

Diabetes insipidus (DI) is a rare condition that causes the body to produce large amounts of dilute urine.
It's not related to diabetes mellitus (the more common type of diabetes), although both conditions share a similar symptom: excessive thirst and frequent urination.

Here's a breakdown of what you need to know about diabetes insipidus:

What causes it?

Diabetes insipidus is caused by a problem with the hormone *vasopressin* (also called antidiuretic hormone or ADH). ADH is produced by the hypothalamus in the brain and stored in the pituitary gland. It helps regulate the amount of water in the body by telling the kidneys to conserve water.

There are four main types of diabetes insipidus, each caused by a different problem with ADH:

Central diabetes insipidus: This is the most common type. It occurs when the hypothalamus or pituitary gland is damaged, interfering with the production, storage, or release of ADH. Causes include:
Head injuries
Surgery near the pituitary or hypothalamus
Tumors in or near the pituitary gland
Infections
Genetic disorders
Stroke
In some cases, the cause is unknown (idiopathic).

Nephrogenic diabetes insipidus: This occurs when the kidneys don't respond properly to ADH. This can be caused by:
Genetic disorders affecting kidney function
Certain medications (e.g., lithium, demeclocycline)
Chronic kidney disease
High calcium levels in the blood (hypercalcemia)
Low potassium levels in the blood (hypokalemia)

Gestational diabetes insipidus: This occurs only during pregnancy. Hormones produced during pregnancy can sometimes break down ADH in the mother's body. It usually resolves after delivery.

Dipsogenic diabetes insipidus (Primary polydipsia): This is caused by a defect in the thirst mechanism in the hypothalamus, leading to excessive fluid intake. Over time, the kidneys can lose their ability to concentrate urine effectively. While technically not "true" DI, the symptoms and treatment approaches can sometimes overlap. This can be caused by mental health issues or structural abnormalities in the brain.

Symptoms

The main symptoms of diabetes insipidus are:

Excessive thirst (polydipsia): People with DI feel extremely thirsty and drink large amounts of water, often preferring cold water.
Frequent urination (polyuria): They produce large volumes of urine, often pale or colorless. This can lead to frequent trips to the bathroom, even at night (nocturia).
Dehydration: Despite drinking a lot, dehydration can still occur if fluid intake doesn't keep up with urine output.

Complications

If left untreated, diabetes insipidus can lead to:

Dehydration: This can cause a range of symptoms, including dizziness, confusion, and even coma.
Electrolyte imbalance: Excessive urination can disrupt the balance of electrolytes in the body, such as sodium and potassium.
Sleep deprivation: Frequent nighttime urination can disrupt sleep.
Developmental issues: In infants and children, dehydration can lead to developmental delays and feeding issues.

Diagnosis

Diagnosis typically involves:

Medical history and physical exam: The doctor will ask about symptoms and medical history.
Urine tests: Urine volume and concentration are measured. A key finding is a large volume of dilute urine.
Blood tests: Blood tests can measure ADH levels, electrolyte levels, and other indicators of kidney function.
Water deprivation test: This test measures urine output and blood ADH levels during a period of fluid restriction. It helps differentiate between the different types of DI.
MRI of the brain: To look for tumors or other structural abnormalities in the hypothalamus and pituitary gland (especially in cases of central DI).

Treatment

Treatment depends on the type of diabetes insipidus:

Central diabetes insipidus: Often treated with desmopressin (DDAVP), a synthetic form of vasopressin. Desmopressin is available as a nasal spray, oral tablet, or injection. The medication helps the kidneys reabsorb water, reducing urine production.
Nephrogenic diabetes insipidus: Treating the underlying cause is key. Medications that may be causing the condition might need to be stopped or changed. Other treatments may include:
Thiazide diuretics: Although diuretics usually increase urine production, they can paradoxically reduce urine volume in nephrogenic DI.
Nonsteroidal anti-inflammatory drugs (NSAIDs): These can sometimes help reduce urine output.
A low-salt diet: This can help reduce the amount of urine the kidneys produce.
Gestational diabetes insipidus: Desmopressin may be used during pregnancy. The condition usually resolves on its own after delivery.
Dipsogenic diabetes insipidus: Treatment focuses on addressing the underlying cause of excessive thirst. This can involve behavioral therapy to reduce fluid intake. Sometimes, a low dose of desmopressin may be prescribed to help the kidneys conserve water.

Important Considerations:

Hydration is crucial: People with diabetes insipidus need to drink enough fluids to avoid dehydration.
Medical alert: Consider wearing a medical alert bracelet or necklace to alert healthcare providers to the condition in case of emergency.
Regular follow-up: Regular monitoring by a doctor is essential to ensure the treatment is effective and to monitor for complications.
Differentiation from Diabetes Mellitus: It is important to emphasize again that diabetes insipidus is a completely separate condition from diabetes mellitus (type 1 and type 2 diabetes). The name similarity is because both conditions can cause frequent urination and thirst. However, diabetes mellitus involves problems with blood sugar regulation due to insulin deficiency or resistance.

If you think you might have diabetes insipidus, it's important to see a doctor for diagnosis and treatment. Self-treating can be dangerous.