Abbreviation: ER, extended release

Additional Information on Non-Insulin Therapeutic Agents

1. Sulfonylureas such as glipizide promote insulin secretion from the pancreas and can be used in cats. Oral glipizide has been used successfully in cats with DM, with benefits being reported in approximately 40% of cats. Transdermal application is unreliable.²⁴ Adverse effects following oral administration include cholestasis, hypoglycemia, and vomiting. There is concern that glipizide may contribute to progression of DM and pancreatic amyloidosis.²⁴ The Task Force only recommends glipizide for use in cats with owners who refuse insulin therapy, and only with concurrent dietary therapy. The initial dose is 2.5 mg/cat orally q 12 hr. The dose can be increased to 5 mg/cat q 12 hr if an inadequate response is seen after 2 wk. If no response is seen after 4–6 weeks, insulin therapy should be instituted.²⁴ If the cat appears to be clinically responsive, the trial can continue for 12 wk to assess response to therapy. Obtaining BGCs is important to confirm therapeutic response. To screen for liver toxicity, regular liver monitoring should be performed. Glipizide should not be used in dogs because they do not have any functional pancreatic beta cells due to the pathogenesis of canine DM.
2. Alpha-glucosidase inhibitors such as acarbose are used to inhibit intestinal glucose absorption and reduce postprandial hyperglycemia. Acarbose has been used in cats along with insulin and a low-carbohydrate diet.²⁴ Acarbose can be used in dogs along with insulin therapy to help improve glycemic control and may decrease the dose of exogenous insulin administration. As a sole agent, acarbose is seldom if ever sufficient, especially in dogs. Advise owners that diarrhea is a possible side effect.²⁵
3. Incretins such as GLP-1 (glucagon-like peptide 1) are metabolic or gastrointestinal hormones that can be used in dogs and cats. They can be used along with glargine (Lantus) insulin therapy and diet in cats to help achieve remission.²⁶ Incretins can help improve diabetic control in cats and dogs. In healthy animals and potentially diabetic cats, GLP-1 increases insulin secretion (in cats it also protects beta cells from oxidative and toxic injury and promotes expansion of the β-cell population) and functions to help delay gastric emptying and increase satiety. In dogs and cats, improved diabetic control is presumed to be via glucagon suppression.²⁷ Currently, although more research is needed, the most promising results have been reported in cats treated with exenatide ER (Bydureon) and in dogs with liraglutide (Victoza).^27,28