Diabetes Mellitus Center The pancreas secretes digestive enzymes into the small intestine but it also secretes hormones into the bloodstream to regulate blood sugar.
The cells of the body require a sugar known as glucose for food and they depend on the bloodstream to bring glucose to them. They cannot, however, absorb and utilize glucose without a hormone known as insulin. This hormone is produced by the pancreas.

Type I and Type II Diabetes Mellitus
Diabetes mellitus is a classical disease in humans. In humans, diabetes is broken down into two forms: Type I and Type II. Also referred to as juvenile onset and adult onset diabetes, or insulin dependent and non-insulin dependent diabetes. With Type 1 the pancreas produces no insulin at all, and in Type 2 the pancreas produces some insulin but not enough. Virtually all dogs have insulin dependent diabetes and must be treated with insulin.
Most cats have non-insulin dependent diabetes.


  • The cells cannot receive glucose from the blood because there is no insulin to permit it.
  • The body is unable to detect the glucose in the blood and is fooled into thinking it is starving.
  • Protein, starch, and fat break-down occur as they do in starvation.
  • Although there is plenty of glucose in the blood, without insulin, glucose cannot get to the tissues that need it.
  • The normal kidney is able to prevent glucose loss in urine. In a diabetic animal, there is so much glucose in the blood that the kidney is overwhelmed and glucose spills into the urine and is lost.
  • Glucose draws water with it into the urine leading to excess urine production and excess thirst to keep up with the fluid loss.

Clinical signs and Diagnosis:

  • Excessive eating
  • Excessive drinking
  • Excessive urination
  • Weight loss

It is usually fairly clear from the history and tests showing high glucose levels in the blood and urine that diabetes mellitus is the diagnosis. Some pets, especially cats can substantially raise their blood sugars from stress causing misleading test results. In this case a fructosamine level should be performed. This test reflects an average blood glucose level over the past several weeks. If the fructosamine is elevated, a one-time elevated glucose can be distinguished from the persistent elevations of true diabetes mellitus. The fructosamine test is also used in monitoring therapy for diabetes.
In dogs, sugars can enter the lens of the eye causing rapid cataract formation. Because a cat's lens is different, this phenomenon primarily occurs in dogs. Another common symptom of diabetes mellitus is urinary tract infection. All the sugar in the urine makes the bladder an excellent incubator for bacteria.

Treatment of Diabetes mellitus requires administration of insulin. This is done by giving injections under the skin every 12hours following a meal for the rest of the patients life. Additionally, careful monitoring of weight, body condition, urination habits and urine quality is important for preventing any complications before they become severe. Patients require repeat blood testing to evaluate glucose levels until the appropriate dose of insulin is achieved. While Diabetes mellitus is not commonly curable, with appropriate treatment and monitoring, many dogs live normal lives. 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. Good glucose control and proper diet can resolve the diabetes in some lucky cats, but virtually never in diabetic dogs.

Once insulin levels are regulated the patient should be monitored at home for excessive thirst, excessive urine production, appetite, and weight loss. Keto-Diastix are used to monitor glucose and detect ketones in urine. Insulin bottles should be replaced every 3 months regardless of whether empty or not.
Bloodwork or Diabetic monitoring profiles should be performed periodically.
It is important for diabetic pets to have their teeth cleaned annually. Dental tartar seeds the body with bacteria and when blood sugar levels run high, infections in important organs can take root. The kidneys and heart are particularly vulnerable.
Regulation is achieved via a balance of diet, exercise, and insulin. Although prescription diets are not always attractive to pets, these foods should at least be offered.
The preferred choice for cats is a low carbohydrate high protein diet. These diets promote weight loss in obese diabetics and are available in both canned and dry formulations. For dogs, high fiber diets are still in favor as fiber seems to help sensitize the pet to insulin.

Infrequently, patients may experience an 'insulin reaction' due to low blood sugar. Signs include weakness, wobbly gait, sleepiness or seizures. If this occurs 2 tablespoons of Karo syrup can be administered by mouth. If no improvement is seen in 10-20 min then veterinary care should be pursued immediately.