Diabetes is a common illness present in middle-aged to older dogs and cats. It occurs when the pancreas does not produce enough insulin. Insulin is required for the body to efficiently use sugars, fats and proteins.  Certain conditions predispose a dog or cat to developing diabetes.

Animals that are overweight or those with inflammation of the pancreas are predisposed to developing diabetes.

Common signs of diabetes are increased drinking, increased urination, appetite is suddenly either ravenous or absent, there is often sudden weight loss or gain, and dehydration. Dogs also commonly develop cataracts which can lead to blindness. Cats can develop weak, stilted or wobbly legs. Cats and dogs will generally show a gradual onset of disease over a few weeks, and it may escape notice for a while.

The diagnosis of diabetes is made by finding a large increase in sugar (glucose) in the blood, and the presence of sugar in the urine. A blood test of other organs is also taken to look for changes in the liver, kidney and pancreas, which can be affected by diabetes.

The condition is easily treated with a combination of diet, exercise, and insulin injections. These act to lower the blood glucose concentration. Without treatment, diabetic animals can develop a syndrome called ketoacidosis that can be deadly. Diabetic pets with ketoacidosis are very ill and may be vomiting and depressed. Untreated diabetic pets are also more likely to develop infections and commonly get bladder, kidney, or skin infections.