Oral Hypoglycemic Drugs for Dogs with Diabetes

I have a 11-year old, male neutered Yorkshire terrier that has been diagnosed with diabetes mellitus. Unfortunately, the owner is not willing to give insulin injections to the dog.  

Will oral hypoglycemic drugs, such as glipizide (Glucotrol), work in dogs with diabetes like they do in cats? I couldn’t find anything in the literature stating that they can be used.

My Response:

Oral hypoglycemic agents, including glipizide, glyburide, and metformin, are only indicated for non-insulin dependent diabetes (type 2 diabetes). Diabetic dogs are always insulin-dependent— in other words, they have no ability for endogenous insulin production (1).

In other words, their pancreatic beta cell has “burned out” and can not longer produce insulin.  Since oral hypoglycemics work by enhancing insulin secretion or its action, these drugs will not work in dogs with diabetes and are never recommended.

Because most diabetic cats have type 2 diabetes, some will respond to these drugs (1). However, because insulin injections offer better control of their diabetic state, these oral agents have fallen out of favor among most veterinarians and are no longer used very often.

Bottom line: Diabetic dogs need insulin injections to do well and survive. They cannot be controlled with oral hypoglycemic drugs.

Reference:

1. Rand JS, Fleeman LM, Farrow HA, et al. Canine and feline diabetes mellitus: nature or nurture? Journal of Nutrition 2004;134(8 Suppl):2072S-2080S.