Symptoms of Diabetes in Dogs and Cats

Common symptoms of dogs and cats with diabetes

Pets with diabetes look unkempt and act lethargic. Because they lose sugar in the urine, and sugar pulls water molecules out with it, they urinate excessively. This causes them to drink excessively. These activities, excessive urination (polyuria) and excessive drinking (polydipsia), are termed PUPD. Pets with diabetes lose weight and lose muscle mass. They may have a lower body temperature than normal pets.

Additional symptoms of diabetes in dogs and cats may include:

  • Excessive drinking & urination (PUPD)
  • Loss of appetite
  • Vomiting
  • Dehydration
  • Depression & lethargy
  • Unkempt haircoat & dandruff
  • Loss of muscles & weakness
  • Weight loss
  • Cataracts
  • Weakness of the back legs
How are pets diagnosed with diabetes?

Diabetes is diagnosed with blood and urine tests. The normal blood sugar (blood glucose) for dogs is 60-125 mg/dl; for cats, 70-150 mg/dl. Diabetes is diagnosed when blood sugars are consistently elevated a significant amount. For example, 220 mg/dl in a dog or 400mg/dl in a cat.

If your pet is anxious when it visits the veterinarian, his or her blood sugar will naturally rise, and the elevation may be as high as the sugar levels in a diabetic pet. To prevent this stress-related elevation of blood sugar, find a veterinarian and a clinic that calms your pet. Or, use a veterinarian who makes house calls. Remember that one or two blood tests showing elevated blood sugar doesn't prove that your pet has diabetes. Blood sugar levels must be consistently elevated, or your pet must have urine tests showing ketones to prove they have diabetes.


There are two ways urine tests indicate diabetes: sugar in the urine or ketones in the urine. Sugar gets into the urine if your pet's blood carries so much sugar that it exceeds the kidneys' ability to hold onto sugar. This is called exceeding the renal glucose threshold. A urine dip stick can identify how much sugar is in the urine, without the pain of drawing blood. A urine dip stick can also identify infections in the urine, which are more likely to occur in diabetic pets because bacteria flourish in a high-sugar environment.

The second urinary indication of diabetes is finding ketones. Ketones are formed when your pet is using (metabolizing) proteins and fats for energy because no sugar is entering the cells. Ketones are a serious indication that your pet has Diabetes and needs insulin.