Diabetes in Dogs: Symptoms, Causes, & Treatment

Up to 1% of dogs might develop diabetes mellitus in their lifetime. While this percentage is luckily quite small, the dog parents whose dogs do develop the disease often struggle to spot the signs and manage the symptoms. 

If this is you, not to worry! Below we’ll take a closer look at diabetes in dogs, from the different types, to the causes, and how you can best spot and manage diabetes mellitus. 

Types of Diabetes in Dogs

Diabetes mellitus is a metabolic disorder that affects a dog’s body’s ability to regulate sugar levels. Diabetes in dogs can happen to them when they’re young, but it’s more often diagnosed in senior dogs. 

There are two main types of diabetes mellitus.

Insulin-deficiency Diabetes

Insulin-deficiency diabetes simply means that the dog’s body doesn’t produce enough insulin (or, often, the body’s immune system destroys the pancreas cells that produce insulin). 

This can happen in type 1 diabetes, which is thought to be caused by an autoimmune reaction. 

In type 2 diabetes, the pancreas may produce less insulin as the disease worsens, which is also considered insulin deficiency. 

Insulin-resistance Diabetes

Insulin resistance is when the dog’s body doesn’t respond well to insulin, which is the hormone that allows glucose to move from the blood into cells to be used as energy. 

To compensate, the pancreas secretes more insulin to maintain normal blood sugar levels. Insulin resistance can lead to prediabetes, type 2 diabetes, and chronic high blood sugar. 

However, not every dog with insulin resistance has diabetes.

7 Causes of Diabetes in Dogs

There are various potential causes of diabetes mellitus in dogs.

1. Obesity

Obesity is a leading cause of insulin resistance. This resistance forces the pancreas to produce more insulin to maintain normal blood sugar levels. The pancreas can become overworked and fail to produce enough insulin, leading to diabetes.

2. Pregnancy

During pregnancy, dogs can develop gestational diabetes, which is similar to what happens in humans. 

The hormonal changes that occur can lead to insulin resistance. If the pancreas cannot compensate for this resistance, diabetes mellitus can develop.

3. Pancreatic Disease

The pancreas is responsible for producing insulin. Pancreatic diseases, such as pancreatitis or pancreatic cancer, can damage the insulin-producing cells in the pancreas. When these cells are destroyed or impaired, insulin production decreases, leading to diabetes.

4. Hypothyroidism

Hypothyroidism slows down the dog’s metabolism and can contribute to obesity, a significant risk factor for diabetes.

5. Dental Disease

Chronic dental disease can lead to systemic inflammation, which may contribute to insulin resistance. The constant presence of infection and inflammation in the body can interfere with the normal regulation of blood sugar, potentially leading to diabetes.

6. Skin Infections

Similar to dental disease, chronic skin infections (characterized by constant itching, rough and red patches, or clear irritation) can cause systemic inflammation. This inflammation can lead to insulin resistance, and if the pancreas can’t compensate by producing more insulin, diabetes can develop.

7. Long-Term Use of Steroid Medications

Steroid medications (like prednisone) can cause insulin resistance by affecting the way cells respond to insulin. Long-term use of these medications can lead to persistent high blood sugar levels, eventually overwhelming the pancreas and causing diabetes.

Symptoms of Dog Diabetes

When being mindful of the potential of diabetes mellitus developing in dogs, it’s important to look out for the symptoms. 

Increased Thirst and Urination

Dogs with diabetes often drink more water than usual. This is because high blood sugar levels cause the kidneys to remove excess glucose from the blood, which also pulls water with it, leading to dehydration.

As a result of the increased water intake, diabetic dogs will also urinate more frequently.

Increased Hunger

Despite eating more, a diabetic dog might lose weight or fail to gain weight. This is because the dog’s body can’t properly use the glucose from food due to insulin deficiency or resistance to up their blood glucose. 

Weight Loss

Even with an increased appetite, diabetic dogs often lose weight. This occurs because the body, unable to use glucose for energy, begins breaking down fat and muscle tissue to meet its energy needs, leading to weight loss.

Lethargy and Depression

Dogs with diabetes may become more lethargic and less active. The lack of proper glucose utilization for energy can make them feel tired and weak.

Cataracts

A dog’s diabetes can cause cataracts to form in the eyes, leading to cloudy or bluish eyes. Cataracts can develop rapidly in diabetic dogs and can lead to blindness if not caught in time.

Infections

Diabetic dogs are more prone to infections, particularly urinary tract infections, skin infections, and dental issues. High blood sugar levels create an environment that helps bacterial growth, making infections more frequent and harder to treat.

Sweet-Smelling Breath

In cases where diabetes isn’t being treated, the dog’s body might start breaking down fat for energy, producing ketones. These ketones can cause a sweet or fruity smell on the dog’s breath, which is a sign of a serious condition called diabetic ketoacidosis.

Are Some Dog Breeds Prone to Developing Diabetes?

Studies have found that there are some genetic defects that can predispose a dog to diabetes. Breeds found to be at a high risk for diabetes include:

• Samoyeds
• Miniature Schnauzers
• Pugs
• Miniature Poodles
• Toy Poodles

On the other hand, the following breeds were all found to be at a low risk for developing diabetes:

• German Shepherds
• Golden Retrievers
• American Pitbulls

Treatments of Diabetes in Dogs

The key to treating diabetes in dogs is to manage blood sugar levels through lifestyle, diet, and medication if necessary. 

Lifestyle and Exercise

It’s important to keep a diabetic dog active. Regular, moderate exercise helps to improve insulin sensitivity and maintain a healthy weight, both of which are important in managing diabetes. 

However, exercise needs to be consistent to avoid fluctuations in blood sugar levels, as the key is to keep them predictable. Sudden intense exercise can cause a drop in blood sugar levels (hypoglycemia) so it’s important to always be monitoring and keep the dog’s strain level moderate.

Diet

Switching a dog’s diet to one appropriate for their diabetes is crucial too. High-fiber, low-fat diets are often recommended, as fiber helps to slow down the absorption of glucose, which helps stabilize blood sugar levels.

Much like exercise, consistency is also key. The dog should be fed the same amount at the same times every day to make sure they maintain normal blood glucose levels and you’re able to predict where they’re at.

Treats should also be in strict moderation.

Medication

The best treatment for diabetes in dogs is often medication in the form of insulin treatment. Insulin injections can be given at home and regulate low blood sugar, keeping the levels normal. These injections are usually given once or twice a day.

Your vet can advise you on how to give these injections for diabetes mellitus and make sure you’re comfortable with the process. 

When to see a vet

If your dog is showing any symptoms of diabetes, you should see your vet to assess the clinical signs. Canine diabetes has a wide variety of causes, so even if you don’t think your dog is particularly at risk, any signs are cause to give your veterinarian a call. They’ll be able to properly assess your pet and decide if they should be tested for diabetes.

They can perform a blood glucose test, where they take a small sample of blood and measure blood glucose levels. Normal blood glucose levels in dogs typically range from 80 to 120 mg/dL. Levels consistently above 200 mg/dL may indicate diabetes, especially when accompanied by clinical symptoms.

They can also do a urinalysis. This can detect the presence of glucose and ketones in the urine. Urine shouldn’t contain glucose, so its presence can indicate that the blood glucose level is too high, and the kidneys can’t reabsorb it. 

Ultimately, your vet will be able to perform the necessary tests and decide if your dog has diabetes, as well as decide on a treatment plan with you.