Types of Insulin for Diabetic Dogs and Cats

Insulin Characteristics Affect Treatment of Canine & Feline Diabetes

Aug 8, 2009

There are several types of insulin commonly used to treat feline and canine diabetes. These include Vetsulin®, glargine (Lantus®), NPH, and detemir (Levemir®) insulin.

Insulin is the drug most commonly used in treating both feline and canine diabetes. Types of insulin are typically characterized by their duration of action:

Pork and beef derived insulins are available only as veterinary products and are not available for human use.

In most dogs, intermediate-acting insulins are the first insulin of choice and usually need to be administered twice daily. In cats, both intermediate- and long-acting insulins are often used. Cats often need to be dosed twice daily with insulin as well. Short-acting insulins are generally only used in the case of diabetic animals which are extremely ill and suffering a keto-acidotic crisis. In this situation, blood glucose levels must be decreased very quickly.

U-100 and U-40 Forms of Insulin

Insulin is generally measured by the number of units administered. However, different types of insulin have different types of unit measurement. Therefore, it is important to match the type of syringe used for administration of the insulin with the type of insulin being administered. Insulins which use a U-100 scale for dosing require U-100 syringes for accurate measurement. Similarly, insulins which are dosed on a U-40 scale must be administered with a U-40 syringe. Using a U-100 syringe for a U-40 insulin may very easily result in a serious overdosage of insulin.

Vetsulin® Insulin in Treating Feline and Canine Diabetes

Vetsulin® is a pork-derived, intermediate-acting insulin. It is known as Caninsulin® in countries outside the United States. Vetsulin® is the only insulin which is approved by the FDA (Food and Drug Administration) for treating diabetes in dogs and cats.

Being a pork-derived insulin, Vetsulin® very closely resembles canine insulin in its molecular composition. For this reason, it has been marketed as the "perfect" insulin for dogs. However, though many veterinarians have had success with using Vetsulin® to treat canine diabetes, not all agree that it is more effective than NPH insulin in treating diabetic dogs.

NPH Insulin and Diabetic Dogs and Cats

NPH insulin is an easily accessible, intermediate-acting insulin which has been used for many years in treating both dogs and cats with diabetes. NPH insulin is now only available as a human recombinant product. However, NPH insulin is readily available through most pharmacies, unlike Vetsulin® which is only available through a veterinarian or veterinary pharmacy.

Glargine or Lantus® Insulin for Treating Dogs and Cats with Diabetes

Glargine insulin, also known as Lantus®, is a long-acting insulin analogue that is becoming increasingly popular for use in cats. It is a "peak-less" insulin which helps to maintain a more constant blood glucose concentration than many of the other insulin types. In cats, glargine administration has been reported to be responsible for higher remission rates in diabetic cats when coupled with a low-carbohydrate, high-protein diet.

However, some veterinarians are wary of glargine, fearing that it is more likely to cause a hypoglycemic crisis for some cats. This may be a significant side effect with the use of glargine. Certainly, frequent blood glucose curves are recommended when glargine is used to treat cats with diabetes. Blood glucose curves may give early warning that remission has been reached and glargine should be reduced or discontinued.

Detemir or Levemir® Insulin in Pets with Diabetes

Detemir (Levemir®) is another long-acting insulin analogue which is similar to glargine. Fewer studies have been done with detemir in diabetic dogs and cats. However, some researchers believe that detemir may be more predictable than glargine in cats and may produce similar remission rates. Though further study of detemir is warranted, it may become more widely used as more information becomes available.

Many different types of insulin are available for treating diabetes in cats and dogs and the knowledge base continues to grow in regards to many of these insulins. For most veterinarians, there is no one best insulin. The correct insulin must be based on the pet's response to the insulin, how well the insulin is absorbed, the onset of action of the insulin for the individual pet, the duration of action of the insulin in the individual pet and both the peak and nadir (lowest) blood glucose levels obtained with the insulin for the pet. Each insulin has advantages and disadvantages which must be examined in light of the individual pet's health status.

Use of glargine and lente insulins in cats with diabetes mellitus, Kelli Weaver et al. Journal of Veterinary Internal Medicine March-April, 2006 Pg. 234-238.

Control of diabetes mellitus in cats with porcine insulin zinc suspension, G Martin, J Rand, Veterinary Record July, 2007 Pg. 88-94.

Evaluation of detemir in diabetic cats managed with a protocol for intensive blood glucose control, K Roomp, J.S. Rand, American College of Internal Medicine 2009 Abstract.

Efficacy and safety of a purified porcine insulin zinc suspension for managing diabetes mellitus in dogs, William Monroe et al. Journal of Veterinary Internal Medicine Sep-Oct, 2005 Pg. 675-82.

The copyright of the article Types of Insulin for Diabetic Dogs and Cats in Pet Diseases is owned by Lorie Huston. Permission to republish Types of Insulin for Diabetic Dogs and Cats in print or online must be granted by the author in writing.