Diabetes Mellitus

I hear a very common complaint from clients that my pet is drinking more water than usual. There are a few common diseases that cause this problem but none more common than diabetes. Diabetes is caused by the pancreas not producing enough insulin. In dogs this disease is not curable but is very controllable with diet and insulin. Due to people’s much longer life span diabetes may be treated for decades and requires a precise balance of diet exercise and insulin. We make dietary changes in dogs to a higher fiber food and place them on insulin. After finding the appropriate balance of food and insulin in the hospital they are discharged and usually on injections twice daily. With minimum care and expense dogs usually do very well and their drinking returns to almost normal. Cats are somewhat more difficult to treat due to their finicky eating behavior. Fortunately, there are some cats that if treated early in the disease will actually go back to producing insulin and not need injections anymore. There is no way of telling which cats will get better and which will need continued therapy. We are not able to treat pets as aggressively or as precise as people, because they are hard to get blood samples on numerous times during the day at home to adjust their food intake and insulin dose. Most pets will live quite normal lives with treatment.

What is diabetes mellitus?

Diabetes mellitus is a condition where there is too much glucose or sugar in the blood. To understand the disease it is best to understand a little bit about how the body functions.

How does the pancreas work?

In the abdomen, the pancreas lives next to the first part of the small intestine called the duodenum. The job of the pancreas is to make and secrete many of the enzymes and substances that are required by the body to digest food and maintain proper blood glucose levels. The enzymes are secreted into the small intestine, but the other substances or hormones such as insulin are secreted into the bloodstream.

Insulin is the hormone needed by every cell in the body except the brain to allow the cell to use glucose as a fuel or energy source.

Glucose comes from the diet. Proteins and starches are broken down to their constituent components many of which are sugars. Insulin is the key that unlocks the cell’s ability to pull them in and utilize them. The amount of insulin in the blood in a healthy pet is regulated by the pancreas and matched to the amount of glucose created by the diet so that the blood sugar or blood glucose remains relatively level.

Fat is digested in a different fashion. One of the byproducts of fat metabolism is ketones. When glucose cannot be used as energy by the cells of the body, the body will increase its production of ketones. For a short period this can be okay, however, the detection of ketones is a sign that something is wrong in the body. Ketones can create many health problems for the body including diabetic ketoacidosis, which is a medical emergency for both people and pets.

What happens when the pancreas doesn’t work well?

Diabetes occurs when there is a lack of insulin produced, when the body fails to bind the insulin and react appropriately, or when the body fails to recognize the increase in blood glucose. This leads to increases in the blood glucose levels. Even though the glucose is in the blood, it is not available to the cells and the body consumes fats and proteins to make energy. The body feels as if it is starving. This leads to weight loss and a ravenous appetite.

The increasing glucose levels in the blood overwhelm the kidney’s ability to keep the glucose in the body and glucose spills into the urine. As the glucose spills into the urine it draws water with it leading to increase urination and thirst.

Do pets get Type I and Type II diabetes?

Just as in people there are different types of diabetes mellitus. Basically those that require insulin, or where almost no insulin is produced. This type of insulin is classified as Type I in people. This type of diabetes is also called Juvenile onset. It requires insulin be given to treat the condition. This type of insulin is the only type of diabetes that dogs get. Type II diabetes is where the body produces some insulin but not enough for the body to control the blood glucose. Cats usually get this type of diabetes mellitus. This might suggest that most cats can get away without insulin injections but that is not the case at all. Instead, for cats, there is potential for the diabetes to actually resolve if the pancreas improves its insulin-secreting ability. Insulin injections are needed to treat most diabetic cats but for some cats, the situation is mild enough for oral medication to suffice. Good glucose control and proper diet can resolve the diabetes in some lucky cats but virtually never in diabetic dogs.

How is it treated?

Pets will generally require insulin as part of the treatment of their diabetes. The type and and amount of insulin that’s right for your pet can vary. After the initial diagnosis, your veterinarian will teach you to give insulin injections to your pet at home. Generally, insulin is given twice daily just under the skin. Often doctors will recommend diet changes both for the type of diet and the amount. Controlling the diet is an important aspect of diabetic management.

In some cases, owners may be able to monitor their pets blood glucose at home as people do, but this is very rare. Too often the pets resists the process of obtaining blood samples and begins to resent mom and dad for their efforts. Sometimes this can even lead to biting and scratching when blood samples are obtained. Much more commonly your veterinarian will have you bring your pet into the hospital or clinic to generate a blood glucose curve. This is a series of blood glucoses obtained over several hours to observe your pets response to insulin and adjust the dosage and type as needed.

What can go wrong?

Always make sure your pet eats before administering their insulin. Things to be aware of include a loss of appetite or lethargy. If these are noted contact your family veterinarian.

If your pet appears drunken or wobbly or has a seizure immediately take your pet to their family veterinarian or the closest emergency facility. This may mean that their blood glucose has dropped too low. This is an extreme emergency. The brain may only use glucose as an energy source and when there is not enough glucose for the brain to function it begins to digest itself for energy. This may results in seizures, blindness, coma and death.

For more information on pets and diabetes check out veterinarypartners.com and search diabetes mellitus, or contact our office and speak with one of our veterinarians.