Diabetes Mellitus

Diabetes mellitus is a chronic endocrine disorder that is quite common in dogs. It is characterized by high blood sugar (hyperglycemia) which results when the pancreas is unable to produce enough insulin to meet the animal's requirements.

Insulin is a hormone which is needed to transport glucose (blood sugar) as well as certain amino acids and minerals through the blood to the cells. When a lack of insulin occurs, glucose cannot move into the cells and the glucose level in the blood rises to abnormally high levels.

Chronic high glucose in the blood and urine can cause severe complications including infections, cataracts, diabetic ketoacidosis, nervous system disorders, pancreatitis, and kidney disease. If left untreated, diabetic animals will suffer from complications and an early death.

Causes: Diabetes is caused by several things including: genetic predisposition, infection, drugs, pancreatic disease, obesity, estrus (heat cycles) in intact females, and concurrent illness.

Who is affected: Although males do develop diabetes, female dogs are twice as likely to be affected by the disease. A genetic disposition towards diabetes is suspected in breeds including the Keeshond, Pulik, Cairn Terrier, and Miniature Pinscher. In addition, Dachshunds, Miniature Schnauzers, Poodles, and Beagles also are frequently diagnosed with the disease. However, any dog can develop diabetes mellitus.

The average age range for the development of diabetes mellitus is four to 14 years, with the majority of cases occurring at six to nine years of age.

Symptoms: Common symptoms include excessive thirst, increased volumes of urine, and urinary accidents. Affected dogs often have weight loss despite an increased appetite. Other symptoms may include loss of vision, tiredness, weakness, and poor coat condition.

Care: There is no cure for diabetes mellitus, but, as with humans, it can be controlled with insulin injections, diet, and exercise management. With such therapy, your dog can lead a happy, comfortable life. Some people with diabetes can use oral hypoglycemic drugs, but these medications typically are not helpful in dogs.

You should not breed a diabetic female. It is extremely difficult to control diabetes during pregnancy, and may cause a life-threatening situation. Intact female patients should be spayed as soon as their diabetes is stable to prevent disruption of diabetic control due to fluctuating hormones.

Once your dog has been diagnosed with diabetes mellitus, its specific insulin requirements need to be determined. As each dog's insulin needs are unique and often vary from day to day, your dog may need to be hospitalized to determine its specific needs. This is accomplished by the veterinarian giving the dog an insulin injection and testing the blood sugar levels at regular intervals throughout the day. These results are used to determine your dog's initial insulin requirements. Because your dog's insulin needs may change once it returns home, periodic reevaluation over the next two weeks is recommended until satisfactory control is achieved. Once control is achieved, further evaluations should be completed every 2-4 months.

Initially, it may be difficult for some owners to give daily insulin injections, but the majority of owners find it is not that difficult.  The insulin is injected just under the skin with a very fine needle and is not painful. It is important, however, that injections be given at the same time each day.

Prognosis: The prognosis is dependent on a number of factors. How well the dog does will depend upon the owner's willingness to treat the disease, the dog's ability to respond to the insulin, the age at the onset of disease, the presence of other disorders, and the development of complications of diabetes.

With dedicated care from the owner, recheck appointments with the veterinarian, and a teamwork approach between the owner and the doctor, most diabetic dogs live healthy lives for many years.

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