Diabetes Insipidus in Dogs

Diabetes insipidus (DI) is rare in dogs and is distinct from diabetes mellitus (DM). There are 2 types of DI and both are related to the pituitary gland in dogs. Your dog will most likely present with issues with urination frequency and amount of water intake. 

Other diagnoses may have to be ruled out due to their similar symptoms, some of those include diabetes mellitus, Cushing’s disease, renal failure, liver disease and infection of the uterus amongst others.

Diabetes insipidus (DI) is an issue with your dog’s ability to control his water intake and urine output. This is a pituitary gland disorder that is rare in dogs and causes your dog’s urine to become diluted due to his inability to concentrate his urine and can lead to dehydration in your dog if left alone.

Symptoms are quite simple to identify, however once again they are similar to other disorders and cannot be used solely to diagnose. 

• Excessive urination (polyuria)
• Excessive drinking (polydipsia)
• It may appear that your dog has incontinence problems, however, it is probably the excessive urination he is experiencing
• Weight loss 
• Failure to thrive 

Types

There are two types of diabetes insipidus and both are directly related to the pituitary gland and how it interacts with the body. 

Central Diabetes Insipidus (CDI)

• Caused by the pituitary gland not releasing enough of the hormone called vasopressin which is an antidiuretic hormone
• May be due to birth defect, trauma, tumor on the pituitary gland, or possible unknown cause
• Found in any breed, gender and age of dog
• Can begin anywhere from 7 weeks to 14 years of age

Nephrogenic Diabetes Insipidus (NDI)

• Caused by your dog’s kidneys not responding to vasopressin that the pituitary gland produces
• May be due to birth defect, drugs, other metabolic disorders
• Found more often in Huskies as a primary diagnosis
• When it is a primary diagnosis it is found in puppies 18 months and under
• Most often it is found secondary to renal failure or metabolic disorders

Causes are related to the pituitary gland and how it is working within your dog’s body. At times there may be an underlying issue such as injury or other medical concerns resulting in secondary DI. Some causes are identified below. 

• Birth defects – Your dog may be born with a pituitary gland that does not work within his body and his production of vasopressin
• Trauma related – Injuries
• Drug related – Possibly side effect of medications your dog is on or has taken
• Tumor on pituitary gland
• Other metabolic disorders being a primary diagnosis

Diagnosing is done by your veterinarian and it will be very important to go in prepared with any symptoms or concerns you may have with your dog. Some things to pay attention to are an increase in urination, incontinence  (or what appears to be incontinence in a trained dog), insatiable thirst, discomfort, and your dog’s inability to relax or remain calm. 

Your veterinarian may want to rule out other disorders and may ask for tests in order do that. Images via x-rays, CT scans or other imaging devices may be used to see if there are any tumors on his pituitary gland as well. A water deprivation test may be used; this test allows your veterinarian to see if your dog produces a better concentration of urine while withholding water or providing the typical medication used to treat DI. Tests may be run to determine your dog’s plasma levels of vasopressin and whether they are absent, too low or too high.

Treatment for CDI is typically done by providing your dog with medications to mimic his pituitary gland hormones via a synthetic hormone replacement such as desmopressin acetate. 

Desmopressin Acetate (DDAVP) is a synthetic form of vasopressin and will help your dog to no longer urinate at such a dangerous frequency. This medication can reverse all of your dog’s symptoms. This medication is administered via the eye or nose. While this medication is a cure for your dog’s DI, it comes with 2 downsides. DDAVP must be given to your dog for the remainder of his life and It can be expensive. 

Treatment for NDI is a bit different as even high doses of DDAVP are only found to be somewhat effective. The use of diuretics, oral salt and chlorothiazide are also used in NDI. The diuretics will help your dog to concentrate his urine reducing the risk of dehydration. 

Your veterinarian may inform you that you can choose to not provide any medical treatment, however your dog will need to be provided with plenty of water at all times, you will not be able to limit his water intake and he will need to frequently use the bathroom.  

If you choose not to provide treatment, it is important to remember that dehydration can lead to death in your dog if left untreated. Without medications to help him concentrate his urine, your dog runs a higher risk of developing dehydration which is why providing him with water at all times is necessary.

Diabetes insipidus is a lifelong diagnosis for your dog and you and he will be dealing with this forever. There is a high rate of recovery for dog’s with CDI if given medication management and symptoms can disappear as soon as 2 weeks after treatment is started.

If your dog is diagnosed with NDI however, it can be a bit trickier. This diagnosis comes with a guarded outcome. If the NDI is secondary to another underlying disorder and that is treated, your dog’s prognosis will be better. However, in the event treatment does not provide your dog relief, he can continue to live a good life with continuous water available to him and monitoring of any symptoms.

Diabetes insipidus is expensive to treat. To avoid high vet care expenses, secure pet health insurance today. The sooner you insure your pet, the more protection you’ll have from unexpected vet costs.