What is Diabetes Mellitus?

Dogs and cats in the waiting roomOnce your Dog or Cat has been diagnosed with Diabetes Mellitus (Discussed further in Part I of our Diabetes Mellitus Blog), how is it treated? The short answer is with injections of insulin and with diet. Diabetes Mellitus is a generally treatable condition caused by an insulin deficiency.  In virtually all dogs, it is classified as Type 1 which means their pancreas can not make any insulin.  Many cats, are classified as Type 2 diabetics which means their pancreas makes some but not enough insulin.  The body’s cells require insulin to make use of the sugar (also called glucose) absorbed from food.  The classic symptoms of diabetes mellitus are increased thirst, increased urination, “ravenous” appetite and weight loss. Please refer to Part I of our Blog on Diabetes for more information on the symptoms and diagnosis of Diabetes.

 How Is Diabetes Treated?

Insulin Injections

Treatment of diabetes mellitus involves administration of the insulin that the pet is not producing on his/her own.  Finding the correct dose of insulin must be tailored to each individual patient and is accomplished by starting at a relatively low dose, then slowly increasing the amount while monitoring the resulting level of blood glucose.  The most common type of insulin used in dogs is a veterinary product called Vetsulin, or a human product called NPH.  In cats, the most common type of insulin is either PZI or ProZinc.

Insulin can only administered in the form of a subcutaneous (below the skin) injection.  Although this may seem overwhelming at first, the owner of a newly diagnosed diabetic pet usually can become significantly more comfortable after only one week of giving injections.  Your veterinarian will serve as a support team to demonstrate how to get started and there are good online videos to demonstrate the process: how to give insulin.

Virtually all cats and dogs will require insulin injections twice a day.  You must use the appropriate size syringe to match the insulin recommended for your pet or an overdose of insulin could occur.  Varying the site that you give the insulin between the nape of the neck and the sides of the chest or abdomen is recommended to avoid scar tissue which could interfere with absorption of the insulin.  Tricks to help make insulin administration more readily accepted by your pet would be to inject them as they are eating, being brushed or offering them a toy.  If your pet is vomiting or refuses a meal, you should postpone that dose of insulin and contact your veterinarian.


Diet plays an important part in helping a diabetic pet stay well regulated.  In cats, a low carbohydrate, high protein diet is recommended which is most commonly found in canned food (vs. dry).  There are prescription veterinary diets made specifically for diabetic cats, but here is a link to a list of over-the-counter cat foods that are low carbohydrate/high protein: http://binkyspage.tripod.com/CanFoodNew.html.  Choosing canned foods with a carbohydrate percentage less than 7 is recommended.  In diabetic dogs, a high fiber diet is recommended.dash and dally photo

How is Diabetes Monitored?

Accomplishing good long term regulation in diabetic pets requires monitoring your pet’s response to their insulin dose.  There are two ways to accomplish this.

  1. You can drop your pet off at your veterinarian for a blood glucose curve where a drop of blood will be analyzed every 2 hours over a period of 10-12 hours to check the blood glucose level.
  2. Or owners can purchase an at-home glucose monitor and perform that same blood glucose curve at home.  To watch a video of an owner performing an at-home blood glucose curve,  go to this online site:  managing diabetes.

Possible Complications

Complications from diabetes mellitus include hypoglycemia (a blood glucose that it too low due to an insulin dose that is too high). Symptoms of hypoglycemia include shaking, weakness, confusion, extreme lethargy and seizures.  You should always have Karo syrup (high in sugar) on hand to be given if these symptoms are noted, and then call your veterinarian.  Other complications include cataracts in dogs and  bladder infections in both dogs and cats.

Diabetes mellitus can seem like a daunting diagnosis at first but with an organized, team-based approach between an owner and their veterinarian, these pets can be cared for effectively and can live a normal life without troublesome clinical signs.