Diabetic cats are quite different because dietary formulation may facilitate reversal of the diabetes.13,14 Low-carbohydrate and high-protein diets are recommended (e.g. Purina Veterinary Diets DM—Nestlé Purina, Prescription Diet m/d—Hill's), although other medical problems such as kidney
disease may limit dietary manipulations. As cats can be finicky, finding a well-tolerated and palatable balanced diet is the
most important consideration. Canned food tends to be lower in carbohydrates than dry food, but dry kitten chow is an acceptable
option if a cat declines one of the therapeutic diabetic diets. It isn't necessary to meal-feed cats receiving PZI or glargine,
as both are well-suited to their natural tendency to eat small amounts frequently. Foods high in simple sugars, such as semi-moist
diets and treats, should be avoided. Obesity is a well-recognized cause of insulin resistance in cats, and gradual weight
loss may improve glycemic control and encourage endogenous insulin production.
Oral hypoglycemic therapy
Dogs with diabetes mellitus are always insulin-dependent, so the oral hypoglycemic drugs are never appropriate. Although some
cats respond to glipizide (thought to enhance endogenous insulin production), most are not adequately controlled, and the
prolonged hyperglycemia may contribute to glucose toxicity and reduce the chance of eventual diabetic remission.15 I would only prescribe glipizide if a client refused to administer insulin, and I would combine it with appropriate dietary
modification and weight loss (if necessary). Acarbose (an enzyme inhibitor that impairs intestinal glucose absorption) may
facilitate glycemic control in cats fed a low-carbohydrate diet.16 However, the effect seems modest, at best, and it cannot be used in place of insulin.
Most dogs and cats with diabetes are successfully managed and continue to be a source of joy and comfort to their families.
Effective client communication is essential, as pet owners need to feel supported by the veterinary team, particularly at
the time of diagnosis. It is important to stress the benefits of regular rechecks and to explain that dose adjustments are
a routine part of diabetic care. Encouraging owners to check glucose concentrations at home can be empowering, and many Web
sites offer guidance and support (e.g.
http://felinediabetes.com/). Reinforce to owners that diabetes mellitus is a treatable disease, and most patients enjoy an excellent quality of life.
Audrey K. Cook, BVM&S, MRCVS, DACVIM (internal medicine), ECVIM-CA
Department of Small Animal Clinical Sciences
College of Veterinary Medicine and Biomedical Sciences
Texas A&M University
College Station, TX 77843
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