Why Is My Dog Drinking Lots of Water?

While it’s perfectly normal for dogs to lap up water from their bowl when thirsty, it can sometimes be concerning for owners if they notice their pups are drinking a lot more than usual.

But how much is too much? And when does it become a problem?

If you’re worried about your dog’s drinking habits, please consult our helpful guide below.

Why is my dog drinking so much?

Increased levels of drinking and thirst in dogs is medically referred to as polydipsia. It often occurs when they are losing excessive amounts of water.

This water loss can occur for a number of different reasons and is one of the most common issues in veterinary medicine.

However, some causes are more serious than others. It is therefore important to take a keen interest in how much your dog is drinking per day, as constant replenishment may signal an underlying health issue.

Here are some of the reasons why your dog may be drinking too much:


One of the most common reasons for your dog needing sudden servings of water is dehydration, which is an issue that can quickly become life-threatening if not treated.

As well as their seemingly non-stop thirst, a severely dehydrated pup will also display fatigued behaviour, a dry tongue and thick jelly-like saliva.

Dog drinks from water bottle

To determine this more accurately, check their skin elasticity with a quick pinch test. If you pinch your dog’s skin and it immediately springs back into position, it is well hydrated. Therefore a severely dehydrated dog’s skin will remain in the pinched position. If this is the case, seek veterinary care straight away.

If your dog is only mildly dehydrated, you can help them yourself by slowly hydrating them with fresh clean water at ten-minute intervals for a few hours. At each interval provide them with just small amounts – one teaspoon for small dogs and one tablespoon for larger ones.

This is to ensure they don’t take on excessive amounts of water too quickly, as this could cause vomiting, and exacerbate their loss of fluids.

Underlying illnesses

If your dog is drinking so much they are beginning to regurgitate or vomit water back up, this is definitely a sign they are drinking too much. At this point, it’s highly likely your dog is suffering from an underlying illness.

Retriver drinks in river

Diagnosing the reason for this behaviour can often be difficult, but more often than not, it is due to one of these medical issues:

  • Liver Disease
  • Diabetes
  • Cushing’s disease (adrenal hormone disease)
  • Cancer
  • Diarrhoea
  • Fever
  • Infection
  • Kidney Disease
  • Hypercalcemia (high blood calcium)
  • Pyometra (uterine infection in unspayed females)
  • Psychogenic polydipsia (psychiatric disorder)

Several of these are very complicated diseases that only get progressively worse. It’s therefore incredibly important to contact your vet if you believe your dog’s excessive thirst could be an indicator of a more serious issue.


If your dog is taking medication for an ailment and has suddenly started lapping up a load, it might be time to check if the drug has any side effects.

Some drugs which are known to cause polydipsia in dogs are:

  • Prednisone or other Anti-inflammatories. These are usually used to treat IBS, asthma and allergies
  • Furosemide and other heart failure drugs. These often list more frequent urination as a side effect, which in turn leads to loss of water and an increase in thirst.
  • Phenobarbital and other seizure medication. These may increase appetite as well as urination and thirst.Bulldog and puppy

When to call the vet about your dog drinking too much

Owners should become concerned if their dog drinks an entire bowl of water at once and then continues to drink every time water is offered.

Other warning signs could be more frequent urination. They may even drink from the toilet or water outdoors in an effort to take on more water.

It’s important to have a general idea of how much your pup drinks a day so that you can spot significant changes if they happen.

How much should my dog drink per day?

In general, a dog should drink about 30ml per pound of body weight a day. This means a small 10lbs pup would need to drink 300ml per day, whereas a large 50lbs dog would need 1.5 litres!

If you notice your pup is starting to take in quantities that far exceed their weight allowance, your alarm bells should start ringing.

It may help you to develop a water bowl routine. Try to fill the bowl to the same measurement each time you refill it and keep track of how many times you have to top it up over the course of the day.

thirsty dog waits for water

Is it normal for my dog to drink so much?

Sometimes, your dog’s excessive drinking is not as serious as you think.

Their drinking could well be explained by one of the three reasons below. However, you should always consult with your vet, just in case.

Natural behaviour

Some dogs may naturally have a real appetite for water and it may well just be a part of their behaviour and character. Large breeds and playful dogs tend to be excessive water drinkers. Their high levels of activity and panting require plenty of replenishment. If you haven’t noticed a sudden, strange increase in their water habits, chances are that’s just how they are.


Whether you feed your dog dry or wet food can have a huge impact on how much water they consume. A mainly dry food diet or diet with high salt is naturally more dehydrating and so your dog will tend to drink more water. If you feel they’re drinking too much, perhaps consider switching to wet food to see if this changes their drinking habits.

Hot weather

During the summer months, your dog will naturally begin panting and drinking more than usual. They are adjusting to the warmer climate. However, hotter weather leaves dogs more prone to dehydration. Be sure to keep an eye out for whether they are beginning to drink far more rapidly than usual.
Mixed-breed dog

What to do if a dog drinks too much water

The best diagnosis can only ever come from a veterinary professional. So if you’ve noticed significant and worrying changes in your dog’s drinking habits, the best thing to do is to schedule an appointment as soon as possible.

However, before getting a diagnosis you should not change your dog’s water rations to restrict intake as it may make things worse. Stopping their access to water will only increase their dehydration.