Diabetes Mellitus

Diabetes mellitus occurs due to an animal’s inability to produce enough insulin and/or use it properly. Insulin is a hormone that efficiently breaks down sugars, fats, and proteins, including the sugar glucose. Without insulin managing glucose levels, sugar accumulates in the blood and spills into the urine and can result in serious health conditions. Pets with diabetes should be evaluated by a veterinarian every two to four months and as health issues arise. Owners should also watch for changes in their pet’s behavior.

What are signs of diabetes in pets?

Untreated diabetic pets are more likely to develop infections and commonly get bladder, kidney, or skin infections. Diabetic dogs can develop cataracts in the eyes. Less common signs of diabetes are weakness or abnormal gait due to nerve or muscle dysfunction. Diabetic pets with ketoacidosis, a serious complication of diabetes, are often very ill and may vomit frequently and be depressed.

What animals are likely to get diabetes?

Animals that are overweight or those with inflammation of the pancreas are predisposed to developing diabetes. Diabetes most commonly occurs in middle age to older dogs and cats. When diabetes occurs in young animals, it is often genetic and may occur in related animals. Diabetes mellitus occurs more commonly in female dogs and in male cats.

How is diabetes diagnosed in pets?

Animals are diagnosed with diabetes when a large increase in blood sugar and a large amount of sugar in the urine are found. A blood screen of other organs is often obtained to look for changes in the liver, kidneys, and pancreas. A urine sample may also be cultured to look for infection of the kidneys or bladder.

How is diabetes managed in pets?

Diabetes is managed by the injection of insulin. In general, cats and small dogs need insulin injections more frequently, usually twice daily, compared to large breed dogs that may only require one dose of insulin daily.

Some diabetic cats can be treated with oral medications instead of insulin injections, but oral medications are rarely effective in dogs. Before you give insulin injections to your pet, your veterinarian should demonstrate the process. The treatment is different for patients with uncomplicated diabetes and those with ketoacidosis. Ketoacidotic diabetics are treated with intravenous fluids and rapid-acting insulin. This treatment is continued until the pet is no longer vomiting and is eating, then the treatment is the same as for uncomplicated diabetes.

What should diabetic pets be fed?

Insulin needs are closely related to the type of food eaten by the pet. Your veterinarian will recommend a specific diet and feeding regimen that will enhance the effectiveness of insulin. Overweight pets will be placed on a weight-reducing diet. It’s important pets with diabetes stick to their diet. Heavy exercise will reduce the amount of insulin needed. Talk to your veterinarian before making changes in diet or exercise.

What are signs of low blood sugar in pets?

There is always some risk a diabetic patient will develop low blood sugar. Signs of low blood sugar include weakness, staggering, seizures, or just being more quiet than usual. You should keep corn syrup on hand to rub lightly on the animal’s gums if they have signs suggestive of low blood sugar.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.