Black and white Jack Russell Terrier, Russell, smiles at the camera

Diabetes in dogs

  • Canine diabetes is an incurable disease which is caused when the body stops making insulin
  • Symptoms include increased thirst, urination and weight loss
  • But it is a common condition in dogs and is manageable but costly to treat, with many patients leading happy and active lives
  • If left untreated, diabetes can cause a number of health issues in dogs


What is canine diabetes?

When dogs suffer from canine diabetes, their pancreas doesn’t produce any – or not enough – insulin, or their body has an inadequate response to the hormone. Insulin is needed to absorb glucose (sugar) into the bloodstream after eating and transport it to cells around the body to enable them to thrive and grow.

Therefore, a diabetic dog’s body cannot control the levels of sugar in its blood and, when elevated, this is called hyperglycaemia. Many dogs can cope with this for a while but they often become seriously unwell if they acquire another illness, such as a urine infection. And diabetic animals are very prone to suffer from other health problems. 

Are there different forms of canine diabetes?

Almost all dogs with diabetes suffer from the type I form of the condition. Like in humans, it means the pet is unable to produce any insulin, so will depend on insulin treatments for life.

Although extremely rare, type II diabetes means the dog’s pancreas produces some insulin but not enough, or doesn’t respond to it properly, which also causes a build-up of the hormone.

What are the main symptoms of diabetes in dogs?

  • Increased urination - caused by the glucose drawing water with it into the urine
  • Excessive thirst - caused by the body trying to keep up with the excess fluid loss
  • Increased hunger – because the body thinks it’s starving
  • Weight loss – because the sugars in the diet can’t be used by the body if there is no insulin, and so they are lost in the urine. This means the dog effectively isn’t getting enough calories and so the body starts to break down the fat reserves as well.  

How is diabetes diagnosed in dogs?

If a blood test shows elevated levels of glucose in the blood and urine, as well as the pet displaying the symptoms above, it’s usually a fairly clear sign that a dog has diabetes.

But increased glucose can sometimes happen due to stress, so if there’s any doubt a test for fructosamine levels may be carried out to test the average blood glucose level over a number of weeks to detect if it’s a persistent, or one-off problem.

What medication will my dog need to control diabetes?

Following diagnosis, an insulin type and dose will need to be decided by your vet – but it may take time to establish the correct dose.

Most pets require injections twice a day, about 12 hours apart, after a meal. You may also need to test your dog’s blood glucose levels at home by taking a small swab of blood with a tiny pin prick.

It’s really important that you stick to a routine and give injections at the same time each day and feed your pet the correct type and amount of food at each meal as advised by your vet. 

Your vet will show you how to give insulin injections and carry out any urine or glucose tests. It’s very important to follow their instructions precisely to make sure your dog’s insulin levels are regulated. Always double check you have the right concentrations of insulin on any syringes.

Many pet owners are understandably concerned about giving injections at soon, but soon get the hang of it.

What are the signs that my dog’s insulin medication isn’t working?

Your pet will require regular check-ups to monitor their condition but always contact your vet for advice if you are worried or your pet seems unwell.

Let your vet know if your pet’s thirst or appetite changes and contact your vet immediately if your pet is dizzy or groggy (this could be a sign that your dog’s blood sugar levels have dropped dangerously low).  

Can changing my dog’s diet help control diabetes?

A balanced diet can also help enormously in regulating your dog’s blood sugar levels. Your vet will advise you on what and how much to feed, and on the timing of meals and injections. High fibre diets are often recommended for dogs with diabetes as it can help limit increases in blood sugar levels compared to a low fibre diet. 

In addition, human titbits should never be given as they can also affect glucose levels.

Are there any long term impacts of canine diabetes?

With the right medication, most diabetic dogs go on to lead happy and active lives. But there are some health problems which they will be more prone to than dogs without the disease. They often develop cataracts rapidly because the sugars affect their eyes. Surgical correction is available but many dogs cope well with loss of sight – their other senses are much more acute than ours!

Urinary tract infections can become a common problem due to the excess sugar in the urine helping bacteria to breed. It is also important for diabetic pets to have their teeth cleaned when necessary because infections in the mouth can cause blood sugar levels to rise.

— Page last updated 24/05/2023