Dr. Lori Wise

Diabetes in Dogs

By Lori A. Wise, DVM, MS - Diplomate ACVIM (Internal Medicine)
Wheat Ridge Animal Hospital
Photo courtesy of Wheat Ridge Animal Hospital

Diabetes mellitus is a common endocrine problem in dogs. It is estimated that one in every 100-200 dogs are diagnosed with this disease. Although any dog can develop diabetes, certain breeds are predisposed: Australian Terriers, Schnauzers, Samoyeds, Miniature and Toy Poodles, Dachshunds, Rottweilers, Miniature Pinschers, Pulis, Cairn Terriers, Keeshonds, Beagles, Pugs, Huskies, and Golden Retrievers. The average age at diagnosis is 7-9 years.

Spayed females are slightly predisposed, and obesity is a risk factor. The cause of diabetes in dogs is not fully understood. Genetic factors are likely. Acute or chronic pancreatitis (inflammation of the pancreas gland) can result in decreased numbers of islet cells and may be a contributing factor in the initiation and progression of canine diabetes.

Diabetic dogs are unable to produce enough insulin from their pancreas. Insulin is a hormone that enables sugar (glucose) to enter the body's cells to provide energy. Diabetic dogs are similar to type I human diabetics, and require that insulin be given by injection once or twice a day.

Common signs that the pet owner may notice include increased thirst, increased need to urinate, and an increased appetite with weight loss. It is an easy disease to diagnose by checking blood and urine glucose levels. If left untreated, the dog will eventually begin to break down his body fat for energy. This results in ketoacidosis, which will cause lethargy, decreased appetite, and vomiting. Ketoacidosis is often an emergency, which requires intensive care and hospitalization. Once the dog is stabilized, the owner will be taught to give the dog insulin injections at home. Most diabetic dogs are fed either canned or dry dog food twice daily.

Normal blood glucose in a dog is between 80 and 120 mg/dl. Diabetic dogs often have a blood glucose over 500 mg/dl. It is usually not possible to maintain the diabetic's blood glucose in the normal range, but a typical goal is to keep it between 100 and 300 mg/ dl for most of a 24-hour period. To determine whether the diabetes is under control, the owner will monitor water drinking, and urination volume and frequency, which should return to near normal levels. Weight gain, if needed, should occur, and the dog's energy level should normalize. Monitoring diabetic patients used to involve having owners catch urine samples and check the urine for glucose. Now, blood glucose meters specifically designed for dogs and cats, which have been validated in veterinary medicine, are available. Owners can be trained to obtain a blood sample from the dog's ear margin, inside of the lip, elbow callus, or paw pad. The blood glucose is measured on this sample. Most dogs are surprisingly amenable to having this done, and over 80% of pet owners are able and willing to monitor their pet's blood glucose long term. The development of cataracts in the eyes of diabetic dogs, which leads to blindness, is a big problem. Achieving good regulation as soon as possible may help delay the development of cataracts. Blood glucose monitoring has greatly improved our ability to regulate diabetic patients, with the result of delaying (sometimes indefinitely) the development of cataracts.

Measurement of serum fructosamine is another parameter that can be used. This value gives an idea of diabetic control for the preceding 2-3 weeks. Owners should be aware of the clinical signs of diabetes and keep their pets at a healthy weight. If diabetes is suspected, your veterinarian can examine your pet and collect blood to help diagnose the condition. With proper treatment and monitoring, most diabetic dogs will have a normal life expectancy.

* Dr. Lori A Wise is a partner at Wheat Ridge Animal Hospital and she is board-certified in internal medicine since 1990. One of her areas of interest is the management of diabetes mellitus in dogs and cats. She has participated in diabetes research and has lectured internationally on the topic.

For more information please visit: www.wheatridgeanimal.com