Overview of diabetes insipidus
Most everyone is familiar with the term “diabetes;” it is a common human disease. But our four-legged friends can get diabetes, too. There are different types of diabetes, one being diabetes insipidus—an uncommon disorder that affects our pet’s ability to conserve water. Because of this disease, your dog or cat urinates and drinks water excessively in an attempt to keep up with the loss of water through the urine.
There are two types of diabetes insipidus. One is due to the insufficient production of a hormone called antidiuretic hormone (ADH) that regulates the body’s ability to absorb water from the kidneys. The other form of diabetes insipidus is caused by the kidneys’ inability to respond to ADH. The kidneys are responsible for regulating the water in your pet’s body. So, without this hormone or the kidney’s response to it, your dog or cat can’t conserve water. Access to water is critical for pets with diabetes insipidus—without it, a dog or cat can become dehydrated in as little as 4–6 hours.
What causes diabetes insipidus?
Generally, diabetes insipidus is considered idiopathic, which means the ultimate cause is unknown. Possible causes include congenital issues, trauma, metabolic conditions, kidney disease, adverse reactions to certain medications, or tumors of the pituitary gland.
Despite the underlying cause of diabetes insipidus, the symptoms are the same. They include:
- Increased thirst/urination (polydipsia/polyuria)
- Dehydration
- Disorientation
- Seizures
- Diluted urine
- Weight loss
Diagnosis of diabetes insipidus
Your veterinarian will perform a thorough physical exam and take a detailed history of your pet’s health. The symptoms of diabetes insipidus are very similar to other diseases, such as diabetes mellitus (“sugar diabetes”), Cushing’s syndrome, liver or kidney disease, Addison’s disease, and hypo-/hyperthyroidism. Your veterinarian may recommend diagnostic tests to identify the underlying cause of your pet’s symptoms.
These could include:
- Chemistry tests to evaluate kidney, liver, and pancreatic function, as well as sugar levels
- Tests to identify if your pet has been exposed to tick-borne or other infectious disease
- A complete blood count (CBC) to rule out blood-related conditions
- Electrolyte tests to ensure your pet isn’t dehydrated or suffering from an electrolyte imbalance
- Urine tests to screen for urinary tract infection and other disease, and to evaluate the ability of the kidneys to concentrate urine
- A thyroid test to determine if the thyroid gland is producing too much (in cats) thyroid hormone
- Abdominal ultrasound to evaluate the health of the kidneys
- Cortisol tests to evaluate your pet’s blood cortisol levels
- Additional tests or medications trails if diabetes insipidus is suspected
Treatment of diabetes insipidus
Treatment of diabetes insipidus will depend on the underlying cause. If the diabetes is a result of too little ADH hormone, your veterinarian might prescribe a synthetic ADH. For pets with this form of diabetes, the prognosis is very good for a normal life expectancy, but lifelong treatment is required. If the diabetes is caused by the kidneys’ inability to respond to ADH, drugs can be used to increase the kidney’s ability to concentrate urine, helping to regulate the body’s water compensation. Unfortunately, this form of diabetes insipidus is much more difficult to manage, medically, so it carries a more guarded prognosis.
If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.