Diabetes Mellitus is a disease which occurs in dogs when the pancreas fails to produce enough insulin. In some cases, insulin production stops all together. Insulin tells the body how to properly use proteins, fats, and sugars. This lack of insulin means the liver doesn’t know when to stop glucose production and no longer stores the glucose properly.

A dog with the disease will have a high level of glucose that far surpasses the normal levels and eventually the kidneys start to leak this excess glucose into the urine. The animal will then begin to urinate large volumes throughout the day, which leads to excessive water consumption and thirst to make up for all the liquid leaving the body.

Unlike humans, animals don’t have Type 1 or Type 2 Diabetes; rather, they suffer from either insulin-resistance diabetes (IRD) or insulin-deficiency diabetes (IDD).

There are a number of factors that play into an animal developing the disease. Certain drugs that are used on an animal, for an unrelated cause, can sometimes interfere with the proper production of insulin. If this goes on long enough, diabetes may develop. One example is Glucocorticoids, which are a type of cortisone drug. As well, animals that have inflammation of the pancreas or are overweight are at higher risk.

The most common cause is when the Beta cells, which are responsible for producing the insulin, are destroyed. They can be destroyed by certain drugs or inflammation of the pancreas, as mentioned above, or by other diseases such as Cushing’s Disease.

The best way to prevent Diabetes Mellitus is to keep your animal at a healthy weight and by avoiding administering progesterone and steroids.

There are a few symptoms that will be present in a dog suffering from the disease. It’s important to note though that these symptoms take place slowly over a few weeks rather than a quick onset:

  • weight loss;
  • increased urination;
  • increased thirst;
  • increased appetite, despite the weight loss;
  • poor coat; and
  • vision loss.

Dogs at Risk
The disease is typically found in middle-aged to older dogs and is more common in females. Breeds to closely monitor are: Poodle, Keeshond, Dachshund, Puli, Beagle, Cairn Terrier, Miniature Schnauzer and Miniature Pinscher.

Testing and Diagnosis
Before any testing is done, there is a good chance you will notice some if not all of the symptoms setting in, such as weight loss, increased thirst, and increased hunger. The veterinarian will perform blood work, looking at the animal’s glucose level. Even if the glucose level comes back as high, it doesn’t automatically mean a diabetes diagnosis. There may be other tests needed for a conclusive answer.

When a conclusive diagnosis has been reached, a serial blood glucose concentration curve will be taken. This is done over many hours as the veterinarian keeps testing the dog’s glucose levels. The reason the veterinarian does this is to figure the best dose, dosage schedule, and insulin for the animal.

Treatment and Prognosis
Treatment involves two steps: figuring out the insulin requirements to stabilize the dog, and then moving forward. Even after a treatment course has been decided on, it’s important to watch for hyperglycemia, which happens when the glucose levels raise above normal levels or even on the top end of normal. Symptoms of hyperglycemia include frequent and/or high volumes of urination, increased thirst, loss of appetite, lethargy or weakness, and/or vomiting.

Insulin is needed to treat diabetes and is given through an injection so it doesn’t get digested in the dog’s intestine. Injections will need to be given once or twice daily. The insulin used is prolonged duration so it will last the required length of time set out in the dosage schedule.

It’s important to be careful with the insulin and not shake it vigorously, heat it or freeze it. If any of these are done, it will damage the insulin. It needs to be mixed before use by gently rolling it in the hands.

Stabilization of the dog’s health means keeping the dog on insulin and maintaining a steady and stable diet. There are some commercial foods meant specifically for dogs with diabetes, but before starting on anything it’s wise to consult with your veterinarian first and decide what’s best.

Return visits to the vet will be necessary to be sure the insulin is working well and is the correct dosage. Sometimes it may end up being too much insulin, resulting in low blood sugar, which is why frequent monitoring is necessary.
When properly treated and controlled, a dog with Diabetes Mellitus can be expected to live just as long as a non-diabetic dog. There is no reason this disease will shorten an animal’s lifespan as it is highly treatable. If left untreated, it can lead to all kinds of complications and problems, including death, in the worst cases.