Diabetes mellitus is a common condition in people and relatively common in cats as well. It is a chronic condition in which the body either isn’t making enough insulin or isn’t responding to the insulin being produced. Insulin, a hormone secreted by the pancreas, helps regulate blood sugar (glucose). Glucose is a by-product of the food our cats eat; it provides energy to the cells in their bodies.
There are two common types of diabetes mellitus. The first type occurs when your cat’s body can’t produce enough insulin; this is called type 1 diabetes. The second type of diabetes occurs when the body doesn’t respond to insulin; this is called type 2 diabetes. This form of diabetes is more common in indoor, less active, and overweight kitties, just as it is with their human counterparts.
The most common symptoms of diabetes are increased thirst (polydipsia) and increased urination (polyuria).
Other symptoms include:
- Weight loss (despite a normal appetite)
Your veterinarian will perform a thorough physical exam and take a detailed history of your pet’s health. The symptoms of diabetes mellitus are very similar to other diseases, such as liver or kidney disease, pancreatitis, and hyperthyroidism. Additionally, sometimes underlying diseases or conditions can cause transient diabetes, and once the primary disease or condition is treated, the diabetes resolves.
Your veterinarian may recommend diagnostic tests to identify the underlying cause of your cat’s symptoms.
These could include:
- Chemistry tests to evaluate kidney, liver, and pancreatic function, as well as sugar levels
- A complete blood count (CBC) to rule out blood-related conditions
- Electrolyte tests to ensure your pet isn’t dehydrated or suffering from an electrolyte imbalance
- Urine tests to screen for urinary tract infection and other disease, and to evaluate the ability of the kidneys to concentrate urine
- A thyroid test to determine if the thyroid gland is producing too much thyroid hormone
- An ECG to screen for an abnormal heart rhythm, which could indicate underlying heart disease
- Abdominal ultrasound to evaluate the health of the kidneys
A good percentage of cats with type 2 diabetes that are treated with twice daily injections of a long-acting insulin preparation, a prescription diet and a weight-loss program, and then closely monitored with bloodwork including blood sugar and fructosamine levels can experience remission of their diabetes, at least for a period of time. Unlike in humans, oral diabetes drugs are not generally effective for feline patients, so are rarely the recommended therapy.
Here are two videos, caring for your diabetic cat and giving injections to your pet, which may be useful to you.
For more information about feline diabetes, visit My Cat Has Diabetes.
If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.
5 Signs Your Cat Has Diabetes
Diabetes mellitus is a chronic, and potentially debilitating, condition in cats. The disorder is most prevalent among obese cats, male cats over eight years old, and those on a diet high in carbohydrates.
Cases of feline diabetes are on the rise, and given the severity of the condition, it is important to take early measures to prevent or manage the health of your diabetic cat.
Typically, diabetes mellitus is a disorder that results when the cells develop a resistance to insulin, a hormone that aids the entry of glucose into the cells. This causes a build-up of the glucose levels in the bloodstream.
Diabetic cats mostly suffer from Type II diabetes, where the body cells can no longer adequately respond to insulin, leading to elevated levels of glucose.
A complete diagnosis always requires a visit to the vet, but a closer look at your cat at home can tell you if there’s a problem. Bring your cat to Dr. Minta Keyes for a check-up if you notice any of these signs:
What is diabetes mellitus?
Diabetes mellitus is a medical condition resulting in an excessive amount of glucose or sugar in the blood. It is literally starvation in the face of plenty, because the body cannot utilize the glucose in the blood stream. Glucose must attach to insulin, which then carries it into the cells to be used for energy. A deficiency in insulin, which is a hormone secreted by the pancreas, leads to too much glucose in the blood and not enough glucose inside the cells where it is needed.
Diabetes mellitus affects an estimated one in four hundred cats, and is seen more frequently in middle to old-age cats and is more common in males than females.
What are the clinical signs of diabetes mellitus?
The clinical signs seen in diabetes are largely related to the elevated concentrations of blood glucose and to the inability of the body to use that glucose as an energy source due to the deficiency of insulin. The most common clinical signs seen in diabetic patients are an increase in water consumption and an increase in urination. Weight loss is also a common feature, and an increase in appetite may be noticed in some cats. Recognition of these signs is variable though, particularly because of the life-style of some cats. If a cat spends a lot of time outdoors, it may drink from ponds or pools of water outside rather than appearing to drink excessively from what is provided indoors. Cats that are fed canned or moist diets receive much of their water intake from their diet and increased water intake will be less easily recognized in these patients.
How is diabetes mellitus diagnosed?
The diagnosis of diabetes mellitus is made based on clinical signs, persistently elevated blood glucose concentration and the presence of glucose in the urine. However, a diagnosis of diabetes cannot be made on a single blood and urine sample as other conditions, in particular stress, may also cause a transient rise in glucose levels. Confirmation of diabetes may therefore require more than one blood sample collected over a period of one to five days. Measuring fructosamine can detect the average glucose levels over the past two weeks.
How is diabetes mellitus treated?
Diabetes mellitus is a treatable condition. Although long-term treatment requires commitment and dedication, it can be rewarding to successfully manage this condition in a beloved pet.
- Removal of Predisposing Causes – Initial steps in treating a diabetic cat may involve removal of any predisposing causes for the diabetes. For example, the administration of some drugs predisposes cats to develop diabetes and withdrawal of these drugs may lead to resolution of the condition. Obese cats are more prone to develop diabetes and weight reduction can lead to resolution of the signs in some cats.
- Dietary Intervention – Recent studies have shown that a small percentage of cats do not handle carbohydrates well in their diets. Due to their unique metabolism, these cats gain weight even on low calorie diets when a large percentage of the calories are in the form of carbhydrates. It appears that these same cats are the ones that are predisposed to diabetes, and many diabetic cats will become non-diabetic when they are put on a “Catkins Diet”. It is very difficult to make a low carb dry diet, as starch is necessary to hold the kibble together. Both the Hill’s m/d dry diet and the Purina DM dry diet are attempts at lowering the carbohydrates, but most endocrinologists think that cats must go to a canned-food-only diet to truly get the carbohydrates low enough to change the metabolism.
- Oral Hypoglycemic Drugs – If the diabetic cat is stable, attempts may be made to treat the condition with oral medications. Acarbose is a drug that inhibits uptake of glucose from the intestines, so it is often used in obese cats. Glipizide is a drug that stimulates release of insulin from the cat’s pancreas, so it might help in borderline cases. Although a small proportion of diabetic cats will respond to an oral hypoglycemic medication, most cats will require insulin injections to control the diabetes.
- Insulin Injections – Most diabetic cats will require once or twice daily injection of a small dose of insulin. Very small needles are available which cause no pain to the cat, and within a short time the procedure becomes routine. Administration times, dosages and type of insulin for your cat will be determined by your veterinarian.
Do treated cats need to be monitored?
During the initial stages of treatment, your cat will require several hospital visits and close monitoring at home until an appropriate insulin dosage is determined. Most cats will achieve initial stabilization within a few weeks, but occasionally individual cats can be very difficult to regulate.
It is important to monitor treatment to make sure it is working properly, and to determine if any insulin dosage adjustments are necessary.
Monitoring can be done in part through the collection of occasional blood samples by your veterinarian, but the most important monitoring is done at home. It is particularly valuable to keep accurate records of the following information (check out logfrogapp.com for an online diabetic log):
- Time of insulin injection
- Amount of insulin injected
- Amount and time of food fed and eaten
- Amount of water drunk
- Approximate volume of urination
*Monitoring Urine Glucose
In addition to these records, it can be valuable to monitor the quantity of glucose passed in the urine as a guide to the effectiveness of the treatment. This is easily done at home using Glucotests, which are confetti-like bits of paper sprinkled in the litter box. These chips change color in the presence of glucose. If urine glucose is consistently high (600), it may be necessary to increase the insulin dose. If urine glucose is consistently low, it may be time to decrease or even stop the insulin. Changes in insulin dosage should not be made based on a single Glucotest reading, and they should not be made without consulting with your veterinarian. Changes in the insulin dose are usually based on trends in urine glucose concentrations, as there is normally some day-to-day variation.
*Monitoring Blood Glucose Levels at Home
Sometimes it is advantageous to be able to accurately determine your cat’s blood glucose levels at home. This is especially important in cats that are difficult to regulate, and in cats that may be becoming non-diabetic. If it is indicated, your veterinarian can provide you with a feline glucometer and train you to obtain a tiny drop of blood from your cat’s ear tip for testing.
Guidelines for Giving Insulin
*We will regulate your cat’s insulin to his or her lifestyle. The more consistent your cat’s routine, the easier it will be to control the diabetes. If possible, we prefer that the cat eats a low carbohydrate meal morning and evening, when the insulin is to be given. That way, the glucose taken in at the meal will start to rise at the same time the insulin is starting to take effect. Also, meal feeding allows you to observe your cat’s attitude and appetite prior to giving insulin. If your cat is sick or not eating, it is better to skip the insulin injection. Appetite is harder to monitor if the cat grazes throughout the day, but it is possible to regulate diabetics that eat multiple meals.
*Insulin dosing should be done at a time that fits into your lifestyle as well as that of your cat. Space out the doses as best you can, and be as consistent as possible, but dosing does not have to be exactly at twelve hour intervals.
*Insulin is a fragile drug, and it can be inactived by heat or vigorous shaking. Pay attention to expiration dates. Get in the habit of drawing up your insulin dose and returning the bottle to the refrigerator before your give the injection, to avoid the mistake of leaving the bottle out too long.
*Most human insulins are given with U-100 syringes (100 units per ml), while most feline insulins are given with U-40 syringes (40 units per ml). Be sure that you are using the correct syringe for your insulin. If you must use a different type of syringe, you must use a conversion factor provided by your veterinarian.
*Always use a new needle and syringe for each dose of insulin.
*Insulin injections are usually given subcutaneously in the nape of the neck, but any place where loose skin is available is acceptable. Occasionally injections must be given intramuscularly.
*When in doubt, do not give insulin!
What happens if my cat receives too much insulin?
If a cat receives too much insulin, it is possible for the blood sugar level to drop dangerously low. For this reason it is important to be very careful in ensuring the cat receives the correct dose of insulin.
The typical signs displayed by a cat with a very low blood sugar level are weakness and lethargy, shaking, unsteadiness and even convulsions. If a diabetic cat shows any of these signs it is important to seek immediate veterinary advice or attention. In mild cases of hypoglycemia, you may observe “wobbling” or “drunken” walk or appearance and the cat may not arouse when you call or pet them. In cases of mild or early hypoglycemia, you should administer approximately a tablespoon of corn syrup, honey or sugar solution by mouth. If more severe signs are displayed such as ataxia or severe incoordination and unsteadiness during walking, or convulsions, you should seek immediate veterinary care. Your veterinarian can advise you on specific emergency treatment of low blood sugar in your cat.
When in doubt, do not give insulin!
Diabetic cats get in trouble if their high blood sugar levels go uncontrolled for a long period of time. High blood glucose for a few hours or a few days is not dangerous. Low blood sugar can be life threatening. If a cat receives too much insulin, of gets insulin when it is not diabetic, or gets insulin when the appetite is poor and the blood sugar is already low, it is possible for the blood glucose level to drop dangerously low. For this reason it is important to remember that a diabetic cat that is acting sick or weak, or vomiting should never get insulin. Talk to your veterinarian!
Diabetic Information Sources
Diagnosing feline diabetes
As soon as any of the above signs are noticed, the cat should be taken to a veterinarian. If the cat is eating and seems mentally normal, it is not typically necessary to go immediately to an emergency clinic. However, things can change relatively quickly with diabetic cats, so it is not advisable to wait several days.
Even though there are classic signs of diabetes in cats, other diseases can act the same way. Kidney disease, an overactive thyroid gland, liver disease and urinary tract infections can all have similar presenting signs and look the same outwardly to the veterinarian. So, to actually diagnose diabetes, the veterinarian will have to perform blood tests and a urinalysis. The blood will show an elevated glucose level and the urine will have glucose in it.
Diabetes cannot be diagnosed simply on an elevated blood glucose because a cat’s glucose level can go up significantly due to stress. The trip to the veterinarian’s office and the drawing of blood can be enough to increase a cat’s blood glucose level. However, the glucose typically does not spill into the urine with such a quick spike. That’s why, to diagnose diabetes, both a blood test and a urinalysis are needed.
There is another blood test that can be used to determine if a cat’s blood glucose has been elevated for longer than the time period of the stressful event. This test measures a cat’s level of fructosamine, a protein that has glucose attached to it, and can give the vet an idea of what a cat’s blood sugar has been over the last 1-2 weeks. It can be used to confirm a diagnosis of diabetes, but is more commonly used when obtaining a urine sample is not possible. Some cats come to the veterinary office with an empty bladder, empty their bladder on the way to the office, or just will not allow a sample to be taken.
What is diabetes?
In the most basic sense, diabetes mellitus is a disorder where blood sugar, or glucose, cannot be effectively utilized and regulated within the body. There are several hormones within the body that play important roles in glucose metabolism. Insulin is one of the most important, if not the most important, and it’s the hormone most central to the development and control of the diabetic state. Glucose fuels the body and insulin is the hormone that helps to get it into most cells within the body.
- Diabetes is often easily diagnosed and controllable. However, when undiagnosed or poorly managed, diabetes can be devastating.
Diabetes can absolutely be managed and your cat can still lead a long and happy life.