Updated March 20, 2021
‘At A Glance (Details Below)’ What To Do
If A Dog Drinks More Than Usual
- When dogs drink more it’s usually hormonal or kidney issues
- These are all easily diagnosed on routine blood & urine testing
- The top cause in small breed dogs is Cushings Disease
- If testing is normal, there’s usually nothing to worry about
Now dive deeper…
I’ve talked before about cats drinking too much water. Now let’s look at the common reasons why dogs drink excessive amounts of water. Just like for cats, drinking too much in dogs is potentially serious and needs investigation.
First, though, how much is too much? The first thing to do is measure the amount.
How Much Water Should A Dog Drink A Day?
A dog under normal ambient temperatures and exercise levels should drink no more than 70mL per kilogram of body weight per day. For example, a 10kg dog should drink less than 700mL per day. Dogs drinking more than this amount should be investigated by a vet.
Most dogs with excessive thirst will drink well over 100mL/kg/day. To measure the actual amount, mark the level of water in the bowl and after 24 hours refill it to the same mark using a measuring jug. Make sure all sources of water have been accounted for and other animals have their own separate water supplies.
If the result is high, here’s what your vet will be thinking about.
Why Dogs Drink Excessive Water
There are five common reasons why you might notice your dog wanting more water without other signs of illness.
- Cushings Disease (hyperadrenocorticism)
- Kidney disease (renal failure)
- Diabetes mellitus (sugar diabetes)
- Using certain drugs like diuretics or steroids
- And appropriate reasons, like a change from a wet to a dry diet, hot weather, increased exercise, suckling puppies
Then there are the common causes where there will also usually be other, more obvious signs of a problem. These include:
- Diarrhoea- read more about treating loose stools here
- Thyroid problems, in this case, hypothyroidism
- Pyometra- a common infection of the uterus only seen in undesexed females
- Advanced liver failure, when there should also be obvious weight loss and poor appetite.
There are in fact many other rare causes such as Addison’s disease, portosystemic shunts, hypercalcaemia (most commonly from anal gland tumours) or diabetes insipidus but don’t worry too much about these. The trick is simply to know that routine blood tests and urine testing should get you a long way towards finding the answer. Whatever the cause, drinking excessively is a sign to take seriously.
Early detection is vital for some diseases. So if you have a dog who starts drinking more, even if they don’t seem unwell, let us take a look! It might be nothing, or it might just be the clue that saves your dog.
Related: Why dogs pee inside
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By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. These help topics are from a series regularly posted on email and Twitter. Subscribe via email here to never miss a story! The information provided here is not intended to be used as a substitute for going to the vet. If your pet is unwell, please seek veterinary attention.