Diabetes Mellitus in Dogs and Cats

What Is Diabetes?

Diabetes mellitus (DM) is an endocrine disorder that results in abnormally elevated blood sugar (glucose). Glucose is a critical energy source for the body and comes from food that is ingested. The pancreas is a small but important organ next to the digestive tract. The pancreas secretes insulin that helps cells absorb and process glucose. In patients with diabetes mellitus, there is an imbalance in the insulin and glucose where either the pancreas is unable to produce enough insulin or the cells do not respond to insulin.

What Are the Clinical Signs?

• Weight loss (especially weight loss with a great appetite)
• Excessive urination – Excess glucose in the blood is filtered into the urine by the kidneys. This results in increased urination and frequent urinary tract infections.
• Excessive drinking
• Cataracts (especially dogs)
• Weakness (especially in the hind limbs)

How Is Diabetes Mellitus Diagnosed?

Fortunately, diabetes mellitus can be diagnosed with routine bloodwork and urine samples done in our hospital. Occasionally, other tests are performed to determine whether there is other underlying disease or infection. Normal ideal blood glucose should be between 70-120 mg/dL. It is common for cats to have a blood glucose up to 250 mg/dL due to stress just from entering the hospital. Therefore, cats often need repeat bloodwork or additional tests to determine whether an elevated blood glucose is due to stress or diabetes.

How Is Diabetes Treated?

 
Hospital Treatment
Some patients are very sick when they present at our hospital and require admission for treatment of diabetic ketoacidosis. This is a life-threatening condition that occurs from chronic unregulated diabetes mellitus.

At-Home Treatment & Long-Term Care
Treatment for Diabetes is Lifelong. Some cats may experience remission and can be managed strictly with diet, eliminating the need for insulin injections. It is important to note that many of these cats may need insulin injections again at a later time.

Insulin – Most patients can be controlled with insulin injections given 1-2 times daily. This may sound intimidating, but most owners quickly become comfortable with administering the injections to their pet. We are happy to coach you through this!
• Please note that insulin must be kept refrigerated.
• There are several types of insulin available for treatment. Insulin is chosen based on effectiveness, length of action (short-acting vs long-acting), availability and cost.
• Be sure that the insulin syringe matches the insulin you are using. Most insulins used in pets are U-40. Human insulin syringes are U-100. Using a U-100 syringe with some veterinary insulins may result in an overdose!
• To administer an insulin injection: Pull the loose skin between the shoulder blades with one hand. With the other hand, insert the needle directly into the “tent” that is created by holding the skin up. Draw back on the plunger to check for blood. If you see blood, remove the needle and do not inject. If no blood is noted, depress the plunger on the syringe and complete the injection.
• It is helpful to feed a small treat at the time of the insulin injection. This serves as a reward to the pet and will help prevent resentment of the treatment.

Diet – Proper diet is essential to management of diabetes. Several prescription diets are available to help reduce blood sugar. The daily ration should be split into two meals that are fed after each insulin treatment.

Cats: Purina DM, Hill’s m/d Glucosupport, Royal Canin Glycobalance, Hill’s Multi-benefit W/D

Dogs: Purina OM, Royal Canin Glycobalance, Hill’s W/D, Royal Canin Diabetic

Treats & Snacks – Diabetic patients should adhere to a strict diet. Treats are not recommended unless specifically approved by one of our veterinarians. In most cases, we recommend the following options:
• Use an approved diabetic canned food to make small meatball treats. These may be kept in the freezer and fed as needed. These also make great treats for hiding medications.
• Green beans may be fed raw or steamed to dogs. These are a great healthy snack that are well liked by most dogs. Do not feed green beans cooked or canned in bacon or pork fat.

Monitoring Response to Treatment

Clinical Signs: It is important to always monitor your pet’s clinical signs. Should you note an increase in thirst or urination, this may indicate that the diabetes is no longer regulated or has a concurrent urinary tract infection. Recurrence of clinical signs should always prompt a medical progress checkup.

Regular Checkups: Diabetic patients will require regular visits to monitor them for appropriate management. During these visits we will perform a blood glucose check and a urine check. In some cases, we may choose to perform a blood fructosamine. This test is not performed on-site and thus, results are not immediately available. Fructosamine helps determine if the blood glucose has been consistently high over the prior week.

Urine Test Strips: Urine test strips can be provided for at-home screening of glucose in the urine. These strips are only effective if the glucose is over 250 mg/dl. However, they are quick and easy to use, and thus, a great at home screening tool if you are concerned that your pet is experiencing high glucose. Pets with a positive urine test strip should be examined.

Continuous Blood Glucose Monitor: Our preference for monitoring is to install a continuous blood glucose monitor. The continuous monitor is a small painless disc that is attached to the patient and then worn at home for a period of 7-14 days. This is much more accurate than spot checks, gives us a much more accurate reading from the pet in their natural environment and regular schedule, and reduces the number of needle punctures. A scanner is used to relay the measurements to an app on a smart phone. This has revolutionized our treatment of diabetes!

Preventative Care

As diabetic, your pet’s immune system will be more stressed and thus more susceptible to infection. Thus, it is imperative that your pet receive regular physical examinations, dental care and preventative care.

Signs of Low Blood Sugar (Hypoglycemia)

It is important to become familiar with signs of hypoglycemia as this can be a serious complication that can result in death. Hypoglycemia may occur from an insulin overdose or if your pet does not eat. Signs of hypoglycemia include: lethargy, weakness, sleepiness, drunken walking, stumbling or seizure and loss of consciousness.

If you note these signs: try to get your pet to eat. If your pet will not eat or is unconscious you may give light Karo syrup, honey or even sugar water. Rub the mixture on the gums or place on the tongue. This will absorb through the mouth and does not need to be swallowed. A ¼ teaspoon or less is usually sufficient for a cat. Large dogs may require more than a tablespoon. You should note improvement within a few minutes. We recommend trying a small amount and then contacting our office for further instruction.

Difficult to Regulate Diabetics

Some patients are particularly difficult to manage. This occurs most often in dogs. Often these patients have concurrent underlying disease such as hypothyroidism or hyperadrenocorticism (Cushing’s). Therefore, if the patient is persistently difficult to regulate we may recommend further testing.