Primary Care

Cat Diabetes

What is Cat Diabetes?

Similar to humans, dogs and cats can get diabetes and there are also two different types. The form in which a pet has absolutely no insulin is called Type I Diabetes (the inability to produce insulin). The other form, Type II Diabetes, occurs when a pet's body makes insulin, but either not enough, or there is a condition present that interferes with the function of the insulin (an insensitivity or resistance to insulin). While virtually 100% of dogs with diabetes mellitus have Type I Diabetes, this form of diabetes is actually considered rare in cats. Approximately 80% (or more) of cats have Type II Diabetes. Due to the differences in these types of diabetes, dogs and cats with diabetes are treated and managed differently.

Could your pet have Diabetes?

As a pet owner, you will likely be the first to spot the symptoms of diabetes. The most common symptoms of dog and cat diabetes are:

Increased Hunger or Appetite (called polyphagia)
Excessive Thirst (called polydipsia)
Increased Urination (called polyuria)
Weight Loss
Weakness or Fatigue
Initially the signs of diabetes are not terribly concerning to most pet owners as their pet is often just eating or drinking more than usual. However, it is important to notify your veterinarian if you detect any of these changes. As with most medical conditions, early detection and treatment of diabetes is recommended for the best possible outcome for your pet. Dogs and cats with diabetes can live happily and healthfully with the proper treatment and monitoring by both you and your VCA veterinarian.

If you recognize any of the symptoms of diabetes in your dog or cat, contact your veterinarian right away to schedule an exam to test for diabetes and other potential causes.


Diabetes mellitus, the clinical name for "sugar diabetes," is a condition that affects the concentration of glucose, a type of sugar, in a cat's blood. Diabetes in cats is rarely the result of a shortage of insulin (Type I Diabetes). More commonly, diabetes results when a cat's body has trouble using the insulin it has made properly (Type II Diabetes).

Insulin affects the way a cat's body uses food. When a cat eats, food is broken down into very small components that the body can use. One component, carbohydrate, is converted into several types of sugars, including glucose. Glucose is absorbed from the intestines into the blood. Once in the bloodstream, glucose travels to cells where it can be absorbed and used as a source of energy-if insulin is present. Without enough insulin, glucose can't enter cells and builds up in the bloodstream. So a cat may act hungry all the time and eat constantly, but still lose weight because its cells can't absorb glucose.

Most cats develop Type II Diabetes, in which their cells no longer respond normally to the amounts of insulin produced by the pancreas. While many cats initially require daily insulin injections, the treatment goal is to correct the factors or conditions causing insulin resistance. If these factors, such as obesity, can be adequately controlled, many cats will experience temporary remission or permanent resolution of their diabetes. Many cats with Type II Diabetes will experience marked improvement in their insulin sensitivity when changed to a species-appropriate high protein, low carbohydrate food. However, not all cats with diabetes are suited to this type of diet. Your veterinarian will conduct a thorough evaluation and recommend the most appropriate diet and treatment for your cat's diabetes.

Diabetes Risk Factors for Cats

  • Older Cats
  • Neutered Male Cats
  • Obesity
  • Physical Inactivity
  • Medications (Steroids and Progestins)

If you think your cat may be at risk, make an appointment today to get your cat checked for diabetes.

We’re here to help! Visit VCApetdiabetes.com to watch a video on how to give an insulin injection, monitor blood glucose with our eDiary, find expert advice and get support from our interactive community to help manage your cat’s diabetes.

Diagnosis and Detection

Diabetes is one of many conditions that can affect your cat and cause visible changes in behavior and other signs. That's why it's important your cat be thoroughly examined by a veterinarian at least once a year or more frequently, if your veterinarian advises.

Cat Diabetes Symptoms

Knowing the signs of diabetes is the first step in protecting your cat's health. If any of these statements describes your cat, speak with your veterinarian about the possibility of diabetes:

  • Drinks more water than usual (polydipsia)
  • Urinates more frequently, produces more urine per day, or has "accidents" outside the litter box (polyuria)
  • Always acts hungry (polyphagia), but maintains or loses weight
  • Is less active or sleeps more (lethargic)
  • Has thinning, dry, or dull hair

When evaluating your cat for diabetes, your veterinarian may ask about these signs and will check your cat's general health to rule out the possibility of other conditions or infections.

A sample of your cat's urine may be tested first for the presence of glucose, ketones, and/or a urinary tract infection. If glucose is present in your cat's urine, your veterinarian will want to determine your cat's blood glucose concentration and fructosamine concentration. If the blood glucose concentration is consistently higher than normal, your cat's pancreas may not be secreting enough insulin or your cat's body is "resistant" to the insulin being produced. Regardless of the cause for increased blood sugar, your pet is suffering from diabetes mellitus.

A diabetes diagnosis is considered definite when glucose is found at a persistently high concentration in blood and in urine.

After the Diagnosis

It can initially be overwhelming when your cat is diagnosed with diabetes. Diabetes is a condition that you can manage successfully and your VCA veterinarian is here to help. Once the diagnosis has been made, ask your veterinarian to schedule a specific "diabetes appointment" during which you can discuss all of your questions or concerns. During this appointment, make sure to address the following topics with your VCA veterinarian:

  • Diet–determining the best type of food for your cat. Cats, as carnivores, often have significant improvement in their blood sugar levels when placed on a high protein, low carbohydrate food. This is also the perfect time to address weight loss if your cat is overweight or obese.
  • Insulin–how to store and administer it properly
  • Hypoglycemia–how to identify and treat potentially life-threatening low blood sugar
  • At-home monitoring you should perform and when you should alert your veterinarian. Ask how you should monitor your cat for the possibility of diabetes remission
  • Recommended veterinary rechecks

For more information on the types of feline diabetes, please read:

  • Diabetes Mellitus in Cats
    Diabetes Mellitus is a disease of the pancreas. In simple terms, it is caused by the failure of the pancreas to regulate blood sugar. Click on the link to learn more.
For additional information on testing, monitoring and administering insulin shots, please read:
  • Diabetes in Cats – Testing and Monitoring
    There are several recommended tests to have done on your cat when Diabetes Mellitus is suspected. Cats can live happily and healthfully with diabetes if proper monitoring is performed by you at home and your cat has regularly scheduled visits with your veterinarian. For the best monitoring of a diabetic cat and the highest chance of diabetic remission, blood glucose can be checked by you at home. Ask your veterinarian if this monitoring approach might be right for you and your cat. Click on the link to learn more.
  • Giving Injections to Cats
    Diabetes Mellitus can be controlled in cats by administering daily insulin injections. Click on the link to learn more.