Why is my dog drinking a lot of water?

Excessive thirst (polydipsia) is a symptom that should never be dismissed in dogs. While a dog that has exercised vigorously or eaten dry food may drink more than usual, consistently increased water intake — especially combined with increased urination — points to an underlying condition that needs investigation.

Medical conditions commonly associated with polydipsia

- Diabetes mellitus – Insufficient insulin production or resistance causes high blood sugar, which the body tries to flush out through increased urination, leading to compensatory thirst.
- Chronic kidney disease – Damaged kidneys lose the ability to concentrate urine, forcing the dog to drink more to maintain hydration. Common in older dogs.
- Cushing's disease (hyperadrenocorticism) – Excess cortisol production causes a classic triad: increased drinking, increased urination, and increased appetite, often with a pot-bellied appearance.
- Pyometra – A serious uterine infection in unspayed females that can cause polydipsia as a secondary sign. A life-threatening emergency.
- Hypercalcaemia – Elevated calcium levels (from various causes including certain tumours) increase thirst.
- Medications – Steroids (corticosteroids) and some diuretics markedly increase thirst.

How to monitor at home

Measure your dog's daily water intake by filling the bowl from a measured jug. A dog should drink roughly 50–100 ml per kg of body weight per day. Track this in Flovvi together with urination frequency to give your vet accurate data.