Diabetes Mellitus in Dogs

The pancreas sits near the stomach, it is responsible for producing insulin. Insulin is a hormone responsible for controlling blood sugar levels and delivering glucose to cells. 


When a dog develops diabetes mellitus the cells responsible for producing insulin are not able to do their job effectively. 


Clinical signs of diabetes in dogs: 


  • Increased thirst (drinking more than normal) 

  • Increased urination 

  • Weight loss 

  • Lethargy 

  • Increased hunger 


If your dog presents with these clinical signs, your vet may suspect diabetes mellitus. They will take a blood sample and urinary samples to achieve a diagnosis. Blood glucose in a dog with diabetes mellitus will be persistently high and there will also be glucose in their urine. Definitive diagnosis of diabetes mellitus in dogs may require blood to be taken to send to the lab, this can take a little longer to get the results. 


Treatment of diabetes mellitus in dogs involves regular insulin injections. 


Diet control in dogs with diabetes mellitus is important, your veterinarian will advise a specific diet to help release sugars more slowly this should be given twice daily at the same time each day. 


Insulin injections have to be given twice a day in dogs with diabetes mellitus, 12 hours apart. This has to be done accurately, if cats are given too much insulin their blood sugar can go too low (hypoglycaemia) and this can be dangerous. 


If a dog is given too much insulin, their blood sugar may drop too low. This is called hypoglycaemia. Always check if the dose of insulin is correct before giving. 


Signs of hypoglycemia: 


  • Wobbly gait 

  • Weakness 

  • Lethargy 

  • Shaking 


This is an emergency, and you should contact your vet immediately. 

Exercise can also affect blood sugar levels as glucose is used during exercise. Try to keep exercise a similar duration and exercise your dog at similar times each day.

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This advice is for UK pets only.Written by vets. Please always seek advice from your own veterinary surgeon if you have concerns about your animal, never try to treat an animal yourself or give any medication without veterinary supervision.