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Understanding Diabetes

Signs of Diabetes in Dogs: Early Symptoms to Watch For

The early warning signs of diabetes in dogs — increased thirst, more urination, weight loss despite a good appetite, and cloudy eyes — and when to see your vet.

Reviewed 2025-07-11
1 min read

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Signs of diabetes in dogs: what to watch for

If something about your dog feels "off" and you've found your way here, trust that instinct — noticing early genuinely helps. The four classic signs of diabetes in dogs are: drinking much more than usual, urinating more often (or having accidents indoors), losing weight despite eating normally or even more, and flagging energy. Any one is worth a vet visit. Together, they're a strong signal.

Why the drinking and urinating?

When there isn't enough working insulin, glucose builds up in the blood and spills into the urine, pulling water with it — so your dog urinates more, and drinks more to keep up. This is usually the first thing owners notice: the water bowl emptying faster, the extra trips outside. A real, sustained change isn't "just the warm weather."

Why is my dog losing weight but still hungry?

This one catches people out. Without enough insulin, your dog's body can't use the glucose in food for energy, so it starts breaking down fat and muscle instead — weight falls even as appetite holds or grows. A dog that's eating well but getting thinner is a classic diabetes picture, and a vet should see them.

Cloudy eyes

Many diabetic dogs develop cataracts — a clouding of the lens — sometimes quite quickly, and for some owners this is the first obvious sign. If your dog's eyes look cloudy or their sight seems to be changing, mention diabetes to your vet specifically.

When to go to the vet

Soon. Diabetes is diagnosed with a simple blood and urine test, and earlier diagnosis means easier stabilisation. If your dog is also vomiting, very lethargic or refusing food, treat it as urgent — that combination can signal a serious diabetic emergency.

If the diagnosis comes, our Just Diagnosed guide walks you through exactly what to do next — and Mello helps you track everything from day one.

Mello uses affiliate links to support our content; we only recommend products we trust. Learn more

Pet Glucometer

If you suspect diabetes, home testing can help confirm symptoms

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Low-Carb Diabetic Dog Food

Essential dietary change for managing diabetes in dogs

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Frequently Asked Questions

Mello is a tracking and communication tool, not a substitute for veterinary advice. Always consult your vet for medical decisions about your pet.

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