Diabetes Treatment in Cats
Dietary management and daily injections of insulin can regulate most diabetic cats, enabling them to lead normal lives. The amount of insulin needed cannot be predicted based on the cat's weight, and must be established for each individual. It is important for the success of initial therapy that the cat be hospitalized to determine his daily insulin requirement. While in the hospital, a glucose curve will be traced, using periodic blood samples to track how your cat responds to insulin and how much insulin will be needed. Most cats need one or two injections a day, and your veterinarian will show you how to give them. Luckily, the amounts are very small, the needles are tiny and very sharp, and most cats tolerate the subcutaneous injections with no problem.
Fructosamine (a test that gives an “average” glucose reading over the previous two weeks, rather than at a single point in time) or periodic blood glucose tests are done at the veterinary clinic to check the correct insulin dose for your cat. At home, you may use special strips to check his urine glucose, or even a special kitty litter additive such as Purina Glucotest Feline Urinary Glucose Detection System, which changes color if there is glucose in the urine. Many owners of diabetic cats do home glucose monitoring using ear pricks and home glucose monitors made for humans.
Cats who are on oral medications may eventually need insulin injections. Oral drugs include glypzide, which enhances insulin production but may be falling out of favor due to side effects, such as vomiting; acarbose, which blocks glucose absorption from the intestines and shows promise; and troglitazone, vanadium, and chromium, which make the cat's body more sensitive to his own insulin.
Because insulin requirements vary with the diet, it is important to keep the cat's caloric intake constant from day to day. It is equally important to maintain a strict schedule for insulin injections and exercise. Cats require small amounts of insulin, so it is necessary to dilute the insulin for accurate dosing. How to prepare and inject the insulin will be explained to you by your veterinarian.
Many cats go through periods when the diabetes seems to correct itself, and they do not require insulin. They may remain in this state of spontaneous remission for varying periods before again needing insulin to control their diabetes. It is important to regularly check the cat's urine for glucose to assist in the early detection of this transient nondiabetic state to avoid insulin overdose.
Dietary management: In the past, diabetic cats were placed on a high-fiber diet that was thought to slow the absorption of nutrients, with the goal of stabilizing blood glucose levels. However, recent research has shown that this is not the ideal diet for diabetic cats. Because cats primarily metabolize protein, not carbohydrates, for glucose, high-protein, low-carbohydrate diets have proven to be more efficiently metabolized and of great help in controlling diabetes. Prescription diets for diabetic cats that fit this profile include Purina DM Feline, Royal Canin Diabetic DS 44, and Science Diet m/d Feline. Some veterinarians also advise their clients to add meat to the cat's diet, and some prefer to avoid dry foods because a carbohydrate source must be added to make the kibble. Consult with your veterinarian for specific guidelines for your cat. Occasionally, an obese diabetic cat responds to dietary management alone and does not require insulin to keep his blood glucose well controlled.
Obesity greatly reduces tissue responsiveness to insulin and makes diabetes difficult to control. Accordingly, overweight cats should be put on a diet until they reach their ideal body weight.
Daily caloric requirements are determined by the weight and activity of the individual cat. Once this is established, the quantity of food offered each day can be determined by dividing the daily caloric requirements by the amount of calories per cup or can of food. To prevent high levels of blood glucose after eating, avoid feeding the whole day's calories at one meal. Divide the daily ration into a number of smaller meals. For cats on once-daily insulin, feed half the food at the time of injection and the rest at peak insulin activity-8 to 12 hours later, as indicated by your cat's glucose curve. With two injections daily, the ration can simply be split in half and fed at the time of the injections. Cats on oral medications should be given small meals throughout the day.
This article is excerpted from “Cat Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.
Copyright © 2008 by Delbert Carlson, DVM, and James M. Giffin, MD. All rights reserved.