What is diabetes insipidus in dogs?

Diabetes insipidus (DI) in dogs is a rare medical condition that is characterized by increased thirst and urination. Because of increased thirst, dogs with DI will drink large amounts of fluids. If dogs with DI do not drink enough fluids to compensate for the lost fluids via urine, they can become dehydrated. Despite sharing the same name, diabetes insipidus is not related in any way to diabetes mellitus. Diabetes mellitus is a chronic condition characterized by high blood sugar levels because the body cannot produce enough insulin or use it properly. Insulin is a natural hormone, which helps process glucose to be used by the body’s cells for energy. DI, however, is a result of problems with water metabolism, not sugar. Therefore, dogs that are diagnosed with DI can still have normal blood sugar levels. DI in dogs occurs when the antidiuretic or ADH hormone is not secreted in sufficient amounts by the brain. It also sometimes occurs if kidney cells do not properly respond to these hormones. This results in excretion of dilute urine and increased thirst in dogs.

Usually, the kidney works by removing excess fluids from the bloodstream. The fluids are then temporarily stored in the bladder in the form of urine. When the fluid regulation system is working properly, the kidneys will store fluids and excrete small amounts of insulin when the dog is dehydrated or thirsty. This normal regulation of body fluids in dogs is achieved by the release of the ADH hormone. The antidiuretic hormone is normally released when the dog is dehydrated. This natural hormone works by triggering the kidney to release body fluids into the blood rather than excreting it as urine. However, in dogs with DI, the ADH hormone does not properly regulate the fluids in the body. This leads to increased passage of dilute urine. Canine diabetes insipidus is not a serious medical condition that is immediately life threatening. However, extreme thirst and frequent urination could be inconvenient for your dog and for you. Some dogs with DI excrete large amounts of urine that they are unable to control the outflow of urine. This may require a visit to a local veterinarian for diagnosis and treatment.

Signs and symptoms of diabetes insipidus in dogs

There are certain signs and symptoms which may be an indication that your dog is suffering from diabetes insipidus. Increased thirst and urination is the common symptom of DI in dogs. Dogs that pass high amount of urine require drinking lots of fluids to avoid getting dehydrated. If you notice this symptom in your dog, it is important you take your dog to see a veterinarian. If left untreated, DI in dogs can eventually lead to dehydration which may result in coma and eventually death.

The following are signs and symptoms of canine diabetes insipidus:

  • Increased urination
  • Increased thirst
  • Weight loss
  • Passing dilute urine
  • Disorientation
  • Dehydration

Causes

It is not yet known what really causes diabetes insipidus in dogs. However, there are two types of DI which normally affects dogs. They are nephrogenic DI and neurogenic DI. Neurogenic DI is caused by a lack of a hormone called vasopressin that helps to regulate water retention in the body. Vasopressin is produced in the part of the brain known as hypothalamus. Therefore, if it is not normally released into the bloodstream, it could be as a result of a brain tumor or head injury. On the other hand, nephrogenic diabetes could occur as a result of deficiency in the ADH hormone. The ADH hormone helps the body to conserve fluids rather than excreting it in form of urine. In case specific cells in the kidney cannot properly respond to the antidiuretic hormone, it may result in excessive passage of fluids in form of urine. The kidney may fail to properly respond to the antidiuretic hormone as a result of a birth defect or adverse reaction to specific types of medications. This could also happen as a result of cysts or amyloidosis in the kidney. Unfortunately, there is no cure for DI in dogs. The good news is that canine diabetes insipidus is a treatable condition. With the right treatment, your dog can live a healthy, happy life.

Treatment

If you notice increased and excessive urination in your dog, it does not necessarily mean that your dog has diabetes insipidus. There are other conditions such as diabetes mellitus, kidney disease and liver problems which share the same symptoms as DI. Your veterinarian will need to carry out different tests to determine what is causing these symptoms in your dog. First, the veterinarian will eliminate the possibility of kidney disease and then evaluate your dog’s ability to urinate through a water deprivation test. In case your dog is not capable of urinating properly, an antidiuretic hormone response test would be required. This will help identify the cause of increased urination in your dog. If your dog is diagnosed with DI, the veterinarian may administer desmopressin acetate to your pet. This medication works by mimicking the action of the antidiuretic hormone that is naturally produced in the body.

Desmopressin acetate comes in the form of a nasal spray or eye drop which you can administer to your dog at home. This medication is usually given once or twice every day. Diabetes insipidus in dogs can also be treated with oral hydrochlorothiazide in combination with a low salt diet. If your dog’s condition is neurogenic, your veterinarian may ask you to give vasopressin injections to your dog. To administer this injection successfully, you may need to practice. You can practice with an orange, where you can inject it with water. This will help give you the confidence to inject your dog with the real medication. It may be scary at first, but your veterinarian will show you how to inject your dog with vasopressin at home. It can be difficult to watch your dog suffer, but when you can administer their medication safely, it can make you feel like you are helping your dog. As you give your dog their medication, make sure your dog can readily access water. Without water and treatment, dehydration can occur.


Disclaimer: Please note that the contents of this community article are strictly for informational purposes and should not be considered as medical advice. This article, and other community articles, are not written or reviewed for medical validity by Canadian Insulin or its staff. All views and opinions expressed by the contributing authors are not endorsed by Canadian Insulin. Always consult a medical professional for medical advice, diagnosis, and treatment.