Diabetes in Cats

It seems that cats can get just about every disease that humans do, and unfortunately, diabetes mellitus is no exception. Diabetes is characterized by high blood sugar caused by either low levels of insulin or from increased cellular resistance to insulin. This latter means that although insulin may be present, that it has less of an effect on the body's cells.

Insulin is produced in the pancreas by a group of cells known as the Islets of Langerhans. Sometimes these cells are damaged due to an autoimmune response and this can lead to a significant reduction in insulin production and secretion. Insulin is important for the uptake of glucose into cells for energy production. In fact, insulin must be present in order for glucose to enter the cells of the body. Without insulin, glucose cannot enter the cells in the body, however, the cells of the brain are able to utilize glucose without insulin being present.

The symptoms of diabetes in cats are weight loss (despite normal eating), increased urination, and excessive thirst. In addition, diabetic cats are at an increased risk of contracting urinary tract infections due to the high amount of glucose present in their urine.

There is evidence that both genetic and environmental factors are involved in whether or not your cat will get diabetes. According to Rand (2004) these are the risk factors for diabetes in cats:

There is evidence that feeding your cat a low-carbohydrate, high-protein diet may help prevent diabetes in cats (Rand, 2004). In addition, helping your cat to maintain a proper weight will also reduce the risk. Overweight cats have a three times greater chance of becoming diabetic. Although having one or more of the risk factors increases your cat's chances for becoming diabetic, in truth, any cat can get it, especially as they get older.

Diagnosis of Feline Diabetes Mellitus

Your veterinarian will draw a blood sample to test your cat's blood glucose level. Significantly higher than normal levels will indicate that your cat has diabetes.

Treatment of Feline Diabetes Mellitus

Treating your cat for diabetes is very important. Cats, like people, or any other animal with diabetes, will not survive long without treatment. Your veterinarian will recommend the treatment regimen that is best for your diabetic cat. Options include pills to increase insulin sensitivity or insulin production, or giving your cat insulin injections. Your veterinarian may also suggest changing your cat's diet. If your cat has to receive insulin injections your veterinarian will show you how to do this.

If your cat has diabetes and your veterinarian tells you that you must give your cat insulin injections then you need to know the following:

First of all, insulin can be very dangerous if given in too large of an amount. Your veterinarian will tell you how much to give to your cat. If you give your cat too much insulin then he or she will go into insulin shock and die. While your cat is becoming regulated on his or her insulin dose, it is best to give your cat the insulin when someone will be home to monitor your cat's condition. It is very important that your cat is eating normally after receiving insulin.

Also, it is best to have an oral feeding syringe handy and some maple syrup in case your cat's insulin level becomes too high, which will cause your cat's blood sugar to plummet to dangerous levels. If this happens your cat may have seizures, and become unable to walk or behave normally, and if some form of glucose isn't given soon your cat may die. If your cat's blood sugar becomes too low after receiving insulin, giving your cat a mouthful of maple syrup will serve to bring your cat's blood glucose levels up. If this happens you should also feed your cat some additional food and call your veterinarian's office.

You will also have to make several trips to your veterinarian to have your cat's blood glucose level checked to determine the appropriate dose of insulin for your cat.

Cats can live happy, healthy lives for years after being diagnosed with diabetes. I had a cat that became diabetic when she was 11 years old. She received injections of insulin (Humulin) twice a day every day for the next five years. She lived to be 16. She was healthy until the age of 16, when she got cancer unrelated to her feline diabetes. Also, she never even realized that she was getting the injections of insulin. I gave them to her when she was preoccupied with eating. She thought I was just petting her.


Rand, Jacquie S. (2004). Canine and Feline Diabetes Mellitus: Nature or Nurture? Journal of Nutrition, 134:2072S-2080S.