Insulin Therapy For Dogs

Insulin is classified based on duration of effect.  Regular or crystalline insulin reaches its peak effect quickly, usually around four hours after administration.  I use it in the clinic to drop glucose levels quickly in patients with uncontrolled diabetes.  It is important to monitor blood glucose levels closely while using this insulin.

Once the blood glucose falls into the normal range, I switch to an insulin that will be used to maintain the patient at home.  For dogs, this usually requires an insulin that has an intermediate effect like NPH (Isophane) insulin.  In most dogs, NPH last 8 to 12 hours so the dog will require twice per day injections.  I start with a low dose and slowly increase based upon the dog’s response. 

The last category are the long-acting insulins, protamine zinc and glargine.  These insulins last a long time.  Sometimes so long, that they may cause a Symogi effect if not monitored carefully.  These types of insulin work well in cats, but not as well in dogs.

Most of my canine diabetic patients maintain the best on a product called Vetsulin made by Intervet/Schering-Plough Animal Health.  The company combined two different insulins, a short-acting amorphous insulin with a long-acting porcine zinc insulin, to give great glycemic control.  Unfortunately, there have been manufacturing problems with Vetsulin and currently, the company recommends transitioning patients to other forms of insulin.  I hope the problems are overcome quickly, as I really like this product.

No matter what type of insulin your dog is on, remember insulin is an active hormone that must be kept refrigerated to be effective.  Also, different insulin products come in different concentrations.  Always match the syringe to the concentration of the product you are using. 

Published by kristennelsondvm

Dr. Kristen Nelson grew up on a farm in Watertown, Minn., where she developed a deep love for animals of all kinds. She received a Doctor of Veterinary Medicine degree from the University of Minnesota, College of Veterinary Medicine. Kris then completed a small-animal internship at the prestigious Animal Medical Center in New York City. In addition to writing and speaking, she cares for small and exotic animals in Scottsdale, Az. Dr. Nelson is widely quoted in the media. Her credits include Ladies’ Home Journal, USA TODAY, the Los Angeles Times and numerous radio and television interviews. Dr. Nelson has written two books, Coated With Fur: A Vet’s Life and Coated With Fur: A Blind Cat’s Love. Kris and her husband Steve share their home with rescued cats, birds and a dog.