Diabetes mellitus is one of the most common hormonal disorders in dogs. Statistics show that one in 400 dogs develop diabetes. So you and your diabetic dog are not alone - many other pet owners are helping their dogs stay healthy and live normal lives with this disease.

Types of Diabetes
Most diabetic dogs have diabetes mellitus (pronounced MEL-uh-tus). In diabetes mellitus, the pancreatic islet cells that produce insulin are destroyed during episodes of pancreatitis or when the immune system attacks them (a form of autoimmunity). Dogs with diabetes mellitus usually require shots of insulin to help their bodies use the energy from the food they eat.

Diabetes insipidus means that either the body is not making enough of the antidiuretic hormone (ADH) that controls water regulation in the kidneys, or that the kidneys cannot respond to ADH. Diabetes insipidus is very rare in dogs; this article addresses only diabetes mellitus in dogs.
What is Diabetes Mellitus?
Diabetes mellitus is the inability of the body to properly use the energy from food. The disease is caused by a deficiency of insulin, a hormone that regulates how the cells absorb and use blood sugar. Insulin is produced by the pancreas, a gland in the endocrine system.
The pancreas serves two functions: one if the production of digestive enzymes; the other is the regulation of blood sugar. The pancreas produces and releases enzymes into the small intestine to break down food into nutrients. It also releases hormones into the bloodstream to help the body use sugar (glucose). One of these hormones, insulin, controls the uptake of glucose into cells. The cells use the glucose as fuel for energy production. When the body does not have enough insulin, the dog may show symptoms of high blood glucose, such as excessive hunger and thirst, increased urination, and weakness in the limbs.

A lack of sufficient insulin causes glucose to accumulate in the blood until the kidneys must use water to flush excess glucose into the urine, causing dehydration. Severe dehydration can causelow blood pressure and possibly shock, so it is important to start diabetes mellitus treatment as soon as possible.
Causes of Diabetes Mellitus
Scientists are not sure about the cause of diabetes; it may be caused by various factors, including a genetic predisposition, diet, or even exposure to certain viruses. But they can point to risk factors such as obesity, a sedentary life style, and genetic history.