OVERVIEW OF DIABETES MELLITUS
WHAT IS DIABETES MELLITUS?
In order to understand the problems involved in diabetes mellitus it is necessary to understand something of the normal body's metabolism.
IN THE DIABETIC ANIMAL THERE ISN'T ENOUGH INSULIN
THUS THE MAIN CLINICAL SIGNS OF DIABETES MELLITUS ARE:
It is usually fairly clear from the history and tests showing dramatic glucose elevations in the blood (and usually the presence of glucose in the urine, too) that diabetes mellitus is the diagnosis. Some pets are able to substantially raise their blood sugars from stress (such as might occur when a sensitive, sick, and anxious patient goes the vet’s office). This could create misleading test results. If there is any question about the diagnosis, a test called a fructosamine level may be requested. This test reflects an average blood glucose level over the past several weeks so if this is also elevated, a one time elevated glucose can be distinguished from the persistant elevations of true diabetes mellitus. The fructosamine test is also sometimes used in monitoring therapy for diabetes mellitus.
TYPE I AND TYPE II DIABETES MELLITUS?
Diabetes mellitus is a classical disease in humans and most of us have heard some of the terms used in its description. In humans, diabetes is broken down into two forms: Type I and Type II. These are also referred to as "juvenile onset" and "adult onset" diabetes or "insulin dependent" and "non-insulin dependent” diabetes. In short, type 1 is the type where the pancreas produces no insulin at all, and type 2 is the type where the pancreas produces some insulin but not enough. Virtually all dogs have "insulin dependent diabetes" and must be treated with insulin. Most cats have "non-insulin dependent diabetes." This might suggest that most cats can get away without insulin injections but that is not the case at all. Instead, for cats, there is potential for the diabetes to actually resolve if the pancreas improves its insulin-secreting ability. Insulin injections are needed to treat most diabetic cats but for some cats, the situation is mild enough for oral medication to suffice. Good glucose control and proper diet can resolve the diabetes in some lucky cats but virtually never in diabetic dogs.
WHAT HAPPENS ONCE A DIAGNOSIS IS REACHED:
First, an insulin type and dose will need to be selected. There are several types of insulins to select from and it is not possible to know how much insulin your individual pet will require. Your veterinarian can make a guess based on what works for other cats and dogs and what has been reported in the literature. Most pets require injections twice a day, approximately 12 hours apart, following a meal.
Some insulins are available from the neighborhood pharmacy and some kinds are available only through veterinary offices and veterinary pharmacies. You will need syringes and bottle of insulin to begin home treatment. Your veterinarian will either provide you with supplies or will give you the necessary prescriptions. Insulin syringes are marked in insulin units so the insulin syringes must match the insulin concentrations (either “U-100” syringes for 100 unit/cc insulins or “U-40” syringes for 40 unit/cc insulins.) Whenever you receive more supplies, always double check these numbers.
Never alter the insulin dose recommended by your doctor. To determine whether dose adjustments are needed (or even a different type of insulin would be more appropriate), the pet will need a "glucose curve" where blood sugar levels are monitored every 2-4 hours or so for 12-24 hours. This kind of testing tells the doctor how long the insulin injection is lasting as well as what the lowest and highest glucoses of the day are. It is important to find out when your pet's curve is due. Often in the beginning, it takes several doses selections and several curves before the right dose is determined.
WHAT ABOUT HOME GLUCOSE TESTING?
Not every pet is amenable to getting pricked with a lancet so that a drop of blood can be harvested for testing. We do not want your pet to fear interaction with you and do not want you to get bitten or scratched; still, some pets are very comfortable with periodic glucose monitoring at home. Home testing may work best for pets that become so agitated by the trip to the vet that their blood sugar levels are altered at the vet’s office and cannot be interpreted. Further, a pet owner can save a great of deal of money if they can produce their own glucose curve at home when the veterinarian requests one.
Also, Sugarcats.net has put together an extensive review of equipment needed for home monitoring as well as picture guides for testing both dogs and cats. Visit them at: www.sugarcats.net/sites/harry/bgtest.htm
If you choose to use a glucometer at home, be sure to keep a log of when your pet was fed, when insulin was given, and what the glucose levels were that you found. Bring this log to your veterinarian when you come for check ups. Glucose levels obtained prior to the first insulin administration of the day are particularly useful. Your veterinarian will also be particularly interested in signs associated with poor regulation: excessive thirst, excessive urine production, excessive appetite, and weight loss.
If your pet is too sensitive for a valid glucose curve at the vet’s office and you do not think you are up to blood sugar testing at home, the fructosamine blood test may be particularly useful. Again, this test looks at average glucose levels so wide fluctuations will not be discovered but at least there is a monitoring option for this situation.
Ketostix can be obtained at any drug store and are used to detect ketones in urine. If it is not difficult to access your pet’s urine, a first morning test is helpful. Remember, the occasional presence of ketones is not a problem but a positive dipstick three days in a row is a criterion for a vet visit.
A bottle of insulin, when stored properly, should last 6-8 weeks.
For more details on insulin administration and storage, please review the Insulin Administration Guide in this center.
WHEN TO RETURN TO THE HOSPITAL/WHAT TO WATCH FOR:
Your pet will probably require re-regulation at some point. During re-regulation periods, expect a curve to be run a week or two after each adjustment in insulin dose.
Bring your pet in for a re-check exam and glucose curve if you note any of the following:
SOME PETS ARE DIFFICULT TO REGULATE
Some pets seem to require re-regulation frequently. There may be an underlying reason to sort out. Here are some possibilities should your pet seem to fit in this category:
For more details on trouble with regulation, please see the section on The “Hard To Regulate Pet” in this center.
FEEDING THE DIABETIC PET
Regulation is achieved via a balance of diet, exercise, and insulin. Realizing that special diets are not always attractive to pets, there are some ideal foods which should at least be offered.
The most up-to-date choice for cats is a low carbohydrate high protein diet such as Hill’s M/D diet or Purina’s CNM-DM diet. (Both these companies use initials to name their prescription foods.) These diets promote weight loss in obese diabetics and are available in both canned and dry formulations. For dogs, high fiber diets are still in favor as fiber seems to help sensitize the pet to insulin.
One should avoid soft-moist diets as sugars are used to preserve them. Breads and sweet treats should be avoided. If it is not possible to change the pet’s diet, then regulation will just have to be worked out around whatever the pet will eat.
For further information you may wish to visit:
A listserv for owners of diabetic pets is also available:
To subscribe, send a message to email@example.com and put the words “SUBSCRIBE PETDIABETES” in the body of the message.
Page last updated: 8/15/10