Diabetes mellitus is a condition that occurs when the body cannot effectively move glucose (blood sugar) into cells. This results in too much glucose in the blood and not enough glucose in the cells.

Without sufficient amounts of glucose, which the body needs for energy, cells cannot function properly. Instead the body has to get energy from other sources, such as muscles and fat. This can result in weight loss, muscle wasting, or lethargy.

Illustrated dog eating food

What Is Glucose?

Glucose is an energy source for the body. Glucose is sugar that is in the blood and comes from food. Every time your dog or cat eats, food is broken down into nutrients that are absorbed by the body. Glucose is one of these essential nutrients. Tissue cells use glucose as a source of energy, or fuel, to function.

What Is Insulin?

Insulin is a hormone produced by the pancreas that allows glucose to enter tissue cells. As glucose enters the bloodstream, the pancreas is triggered to produce insulin. In a healthy pet, insulin attaches itself to receptors on the cell and acts as a key to allow the glucose to enter the cell and be used for energy.

In diabetic pets, like diabetic humans, either the insulin does not bind properly with cell receptors or the pancreas does not produce enough insulin. Therefore, cells do not respond to insulin properly, causing glucose to build up in the blood stream, where unfortunately it doesn’t do its job as a source of energy for the body.

Treating Your Pet's Diabetes
Health & Wellness
Treating Your Pet's Diabetes
Could your pet have diabetes?
Could your pet have diabetes?

Type 1 vs. Type 2 Diabetes in Pets

Type 1 Diabetes

  • Occurs when the pancreas does not produce enough insulin.
  • Most common in dogs.

Type 2 Diabetes

  • Occurs when the pancreas produces enough insulin, but the cells do not properly respond to insulin.
  • Most common in cats.

Living With Pet Diabetes

While diabetes can be a serious health condition, it is not a death sentence for your pet. With proper management—including at-home blood glucose monitoring, insulin, diet and exercise—you can help your pet live an active and happy life with diabetes.


Richard E. Goldstein, DVM, DACVIM (SAIM), DECVIM‑CA

Dr. Goldstein graduated from the Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, in 1993 and completed a residency in Small Animal Internal Medicine at the University of California, Davis. He was a faculty member at Cornell University, College of Veterinary Medicine from 2001-2011, then joined the Animal Medical Center as Chief Medical Officer.

He is currently the Chief Medical Officer and Executive Director of Medical Affairs, Zoetis Petcare. His clinical and research interests are the infectious renal and genetic diseases of dogs and cats. He has published over 70 peer reviewed manuscripts and book chapters and is the recipient of the Norden Distinguished Teaching Award.