Dogs drink more water because of heat, exercise, salty food, or conditions like diabetes or kidney disease. See a vet if the increase is sudden.
Normal intake
About 1 ounce of water per pound of body weight daily, or roughly 0.5 to 1 ounce per pound.
Common reasons
- Heat and exercise.
- Salty food or dry kibble.
- Medications such as steroids.
Medical causes
Diabetes, kidney disease, Cushing’s disease and urinary infection.
See a vet
If your dog drinks more than 100 ml per kg a day, or the increase is sudden or comes with more urination.
Normal intake
A general guideline is about 1 ounce of water per pound of body weight per day (about 60 to 70 milliliters per kilogram). A 50 pound dog would drink about 50 ounces (1.5 liters). Drinking more than 100 milliliters per kilogram per day is considered excessive (polydipsia).
Normal reasons for more drinking
- Hot weather and exercise.
- Salty or dry food (kibble contains about 10% moisture versus 75% in canned food).
- Pregnancy or nursing.
- Medications such as steroids (prednisone), diuretics and some anticonvulsants.
- Excitement or boredom.
Medical causes
- Diabetes mellitus, with increased urination and weight loss despite good appetite.
- Kidney disease.
- Cushing’s disease (hyperadrenocorticism), common in middle aged and older dogs, with pot belly and hair loss.
- Urinary tract infection.
- Liver disease.
- Pyometra in unspayed females, an emergency.
- Hypercalcemia.
- Addison’s disease, less commonly.
Measure at home
Fill a bowl with a measured amount of water and measure what is left after 24 hours. Take this to the vet.
Do not restrict water
Do not limit water without veterinary advice, as dehydration can be dangerous.
See a vet if
The dog drinks much more than usual for more than a couple of days, has accidents in the house, loses weight, vomits, has bad breath, lethargy, or changes in appetite. Diagnosis may involve blood tests, urinalysis and imaging.
Treatment
Depends on the cause: insulin for diabetes, diet and fluids for kidney disease, antibiotics for infections or medication for Cushing’s disease.
Normal intake and excessive drinking
A general guide is that dogs drink about 1 ounce of water per pound of body weight daily, or about 50 to 60 ml per kilogram. Active dogs, hot weather, dry food diets, nursing mothers and salty treats increase thirst. Polydipsia, or excessive drinking, is usually defined as more than about 100 ml per kilogram per day (about 1.5 ounces per pound). Measure by filling a bowl with a known amount and checking what remains after 24 hours.
Medical conditions and vet care
Excess thirst can signal diabetes mellitus, Cushing disease, kidney disease, liver disease, urinary tract infection, uterine infection (pyometra) in unspayed females, Addison disease or high calcium. Medicines such as prednisone and diuretics also increase thirst. Never restrict water without veterinary advice. See a vet if thirst is new, persistent or accompanied by increased urination, accidents in the house, weight loss, vomiting, lethargy or a change in appetite. Blood and urine tests find most causes.
Based on data from the American Veterinary Medical Association and the American Kennel Club
