Diabetes mellitus is one of the most common hormonal disorders in dogs. Statistics show that one in 400 dogs develop diabetes. So you and your diabetic dog are not alone - many other pet owners are helping their dogs stay healthy and live normal lives with this disease.
Types of Diabetes
Most diabetic dogs have diabetes mellitus (pronounced MEL-uh-tus). In diabetes mellitus, the pancreatic islet cells that produce insulin are destroyed during episodes of pancreatitis or when the immune system attacks them (a form of autoimmunity). Dogs with diabetes mellitus usually require shots of insulin to help their bodies use the energy from the food they eat.
Diabetes insipidus means that either the body is not making enough of the antidiuretic hormone (ADH) that controls water regulation in the kidneys, or that the kidneys cannot respond to ADH. Diabetes insipidus is very rare in dogs; this article addresses only diabetes mellitus in dogs.
What is Diabetes Mellitus?
Diabetes mellitus is the inability of the body to properly use the energy from food. The disease is caused by a deficiency of insulin, a hormone that regulates how the cells absorb and use blood sugar. Insulin is produced by the pancreas, a gland in the endocrine system.
The pancreas serves two functions: one if the production of digestive enzymes; the other is the regulation of blood sugar. The pancreas produces and releases enzymes into the small intestine to break down food into nutrients. It also releases hormones into the bloodstream to help the body use sugar (glucose). One of these hormones, insulin, controls the uptake of glucose into cells. The cells use the glucose as fuel for energy production. When the body does not have enough insulin, the dog may show symptoms of high blood glucose, such as excessive hunger and thirst, increased urination, and weakness in the limbs.
A lack of sufficient insulin causes glucose to accumulate in the blood until the kidneys must use water to flush excess glucose into the urine, causing dehydration. Severe dehydration can causelow blood pressure and possibly shock, so it is important to start diabetes mellitus treatment as soon as possible.
Causes of Diabetes Mellitus
Scientists are not sure about the cause of diabetes; it may be caused by various factors, including a genetic predisposition, diet, or even exposure to certain viruses. But they can point to risk factors such as obesity, a sedentary life style, and genetic history.
The following are risk factors for diabetes in dogs:
- Age — Dogs are generally over seven years of age, but are occasionally diagnosed at a much younger age. On average, dogs are diagnosed between the ages of 8 and 12.
- Gender — Female dogs have diabetes at almost twice the rate of males.
- Breed — Although any breed of dog may get diabetes, several studies indicate that some breeds tend to be diagnosed with diabetes more often, which may point to a genetic predisposition to the disease.
The breeds that are at higher risk include:
- Cairn Terrier
- Schnauzer (miniature and standard)
Some of the symptoms that can indicate diabetes are:
- Low energy, lethargy
- Losing weight
- Eating excessively, not eating, or other changes in interest in food
- Drinking large amounts of water
- Urinating frequently, which may cause waking up at odd times to urinate
By the time you notice that your dog's eating habits have changed, that he's drinking excessive water, or even vomiting, your pet may be losing weight and getting lethargic. Because diabetes can be controlled more easily with an early diagnosis, it is important to go to a veterinarian as soon as you notice these symptoms.
The longer symptoms persist without a diagnosis, the more the blood glucose level increases and damage can occur in the bladder, kidneys, liver, and eyes. Dogs with diabetes can also have a decreased resistance to bacterial infections.
Tell your veterinarian all the symptoms you have observed in your dog, including the physical symptoms and any changes in mood, behavior, and energy. Your veterinarian may suspect diabetes right away and take a quick blood glucose test like the ones that human diabetics use. This kind of test can give an immediate reading of current blood glucose, but is not a definitive diagnosis since elevated blood glucose readings can be caused by problems other than diabetes.
Your veterinarian will know about many other health problems that cause similar symptoms, such as Cushing's Disease, and may order a blood test for blood glucose levels along with other tests of kidney and liver function, etc.
It may take several days to get the blood test back from the lab. Your veterinarian will want to meet with you to discuss the findings and the care you need to give your pet.
Treatment for most dogs includes insulin therapy, weight control, dietary therapy and exercise.
Most diabetic dogs need insulin, given in daily injections. Depending on the type of insulin your veterinarian suggests, your dog will need one or two injections per day.
Your veterinarian will show you how to handle insulin and administer shots to your dog. The veterinarian may have you practice giving the shot in the office, to make sure you know how to do it and to answer any questions.
Insulin shots are given under the skin, so you won't have to find a vein. Some veterinarians suggest you give shots in the buttocks area, others suggest the loose skin around the neck. Ask which area your veterinarian recommends for your pet.
Too Much Insulin
The greatest threat to your dog's health related to insulin is getting too much insulin. This causes blood glucose levels that are too low (hypoglycemia), which can make the dog very sick and can result in death. Just as human diabetics carry a candy bar or orange juice to treat their low blood glucose, you should carry corn syrup or sugar pills with you for your diabetic dog.
Symptoms of low blood glucose include:
- Dizziness or unsteady gait
Every dog shows a different combination of these symptoms. React immediately to the symptoms by giving your dog corn syrup or sugar pills. It's important to make sure your dog ingests glucose in one of these forms as soon as possible. You can dilute the corn syrup in water and let your dog drink it. If the dog does not willingly drink it, administer it orally using a turkey baster. Corn syrup absorbs into the blood stream through the tissues of the mouth, so it is immediately effective.
You should quickly see a change in the dog's symptoms and behavior since this treatment increases the blood glucose right away. Keep in mind that elevated blood glucose for a short time is much less dangerous than low blood glucose. To prevent low blood glucose, it's generally better to err on the side of too little insulin rather than too much.
A healthy weight for your dog will help you control the diabetes and keep your dog active. A diet that is low-fat, moderate complex carbohydrate, and high-protein is recommended. Your veterinarian can suggest changes in diet or a prescription food for your dog.
Make sure to feed your dog at specific times each day and stick to these prescribed times. Resist the temptation to feed extra food, such as table scraps, and ask others in your household not to give treats that may alter blood sugar or increase weight. Consult your veterinarian about acceptable treats.
Check with your veterinarian about other medications your dog is taking. Some medications should be avoided in diabetic dogs.
Consequences of Diabetes
Diabetes can cause many other health problems when not properly regulated. Some of the complications include:
- Eyes — diabetes can cause or worsen cataracts
- Kidney disease
- Liver disease
- Limbs — high blood glucose can cause weakness and instability in the legs
- Increased susceptibility to infections
Most dogs are diagnosed with diabetes when they are between 8 and 12 years old. Some are much younger, but with the consistent care, you can expect your pet to live a normal life and be active and healthy.
This article is approved by Ellen Miller, DVM, MS, Diplomate ACVIM of Flatiron Veterinary Specialists
Please consult your veterinarian for diagnosis and before beginning any treatment program.