VET APPROVED

REVIEWED & FACT-CHECKED BY

Dr. Amanda Charles

BVSc MRCVS (Veterinarian)

The information is current and up-to-date in accordance with the latest veterinarian research.

Learn more »

Your dog always needs access to fresh drinking water daily. If you have more than one dog, you might need to fill up their water dish more than once a day. Dogs drink water for the same reason we do: to quench their thirst for various reasons. However, if you notice that your dog is drinking far more water than usual, you might wonder if something could be wrong.

Many things can affect your dog’s thirst, including the ambient temperature and their activity level, but excessive drinking is also a common sign of medical problems. If you notice consistent and significant increases in the amount your dog is drinking, or they are showing any signs of being unwell, you should consult with your vet as soon as possible.

Below are nine of the common reasons your dog may be drinking so much water.

What Is Polyuria and Polydipsia?

The medical term used to describe excessive thirst is polydipsia (PD). Polyuria (PU), is excessive urine production. As you might expect these two signs usually occur together and veterinarians often abbreviate and refer to this as PU/PD.

Medical conditions that cause increased drinking in dogs most often cause the kidneys to make more dilute urine, and so the dog has increased thirst and drinks more. So it is usually the increased urine production that happens first, and the increased drinking is to compensate.

There are many conditions that have increased thirst and urination as part of their clinical signs, so it is essential to consult with your veterinarian for an accurate diagnosis and treatment. Under no circumstances should water ever be withheld from your dog.

The 9 Common Reasons Your Dog Is Drinking So Much Water

1. Hot Weather and Increased Activity

Just like with us, a temporary increase in your dog’s thirst can be due to warmer weather or exertion. Rather than sweating, dogs lose water and cool off primarily through panting, and so will drink more to replenish themselves. It’s essential to make sure they have clean , fresh water readily available.

It’s also important to be aware of the signs of dehydration in dogs.

If you notice any signs that might indicate your dog is dehydrated, then contact your vet straight away.

2. Diet

Changes to your dog’s diet can also cause them to drink more. Dry food contains much less water than canned foods, and so if your dog is eating solely or mainly dry food, they will need to drink more to stay hydrated. Another reason for drinking more is if your dog has ingested salty foods or snacks, especially human foods like potato chips.

3. Diarrhea or Vomiting

One common reason your dog might be drinking more than usual is because they are compensating for the loss of fluid due to diarrhea or vomiting. Like humans, dogs can experience stomach upset that leads them to have runny bowel movements or vomiting. Even if they have a stomach upset for just part of the day, this can lead to the need to drink more water.

Unfortunately, diarrhea and/or vomiting are common signs of illness, parasites, or other issues. The dog could have eaten something outside, like feces, dead animals, or garbage. If the dog has had diarrhea for more than 24 hours, or is showing other signs of being dehydrated or unwell, your vet should be contacted.

4. Medication

Another reason your dog might be so thirsty is the medication they have been prescribed. Your veterinarian should have discussed some of the potential side effects of medications with you; however, it can be hard to remember all the side effects that could occur.

The above is not an exhaustive list of medications that could lead to excessive thirst so it is best to speak to your veterinarian.

5. Kidney Failure

Also known as renal failure, kidney failure prevents the kidneys from concentrating urine effectively. This means that larger amounts of more dilute urine are passed, and dogs have an increased thirst and drink more water to try and replace lost fluids.

6. Diabetes Mellitus

Diabetes Mellitus is a disease in which the body does not produce a sufficient amount of insulin, causing glucose levels to rise. As the body tries to get rid of the excess sugar in the urine, the individual affected will urinate larger amounts more frequently, resulting in more drinking.

If you think your dog might be diabetic, you can also look for the following signs (in addition to excessive drinking) and contact your vet straight away:

7. Cushing’s Disease

Cushing’s disease is when there is an overproduction of the stress hormone cortisol. This is more common in older dogs, aged 7 to 12. Cushing’s disease can lead to a multitude of signs along with drinking and urinating more, including increased appetite, a “potbelly”, lethargy, thin skin, and hair loss.

While Cushing’s disease can happen to any breed, some are more predisposed to it, like American Staffordshire Terriers, Boxers, Boston Terriers, Dachshunds, and Poodles. So particularly if you have one of these breeds, they are over 7 years old, and you notice they are urinating and drinking more than usual, you should reach out to your vet to see if they want to conduct a full assessment on them.

8. Ingesting Toxins

As we had mentioned, if your dog eats something they should not have, this could lead to a stomach upset. However, your dog might have ingested something more serious, leading to an increase in drinking. Ingesting NSAIDs, grapes and raisins, rat poison, or an excessive amount of vitamin D can lead to kidney failure (which we already discussed). These are not the only toxins and dangerous items that can cause polydipsia.

9. Pyometra

If you have an unspayed female dog, they are at risk of pyometra, which is a life-threatening infection of the uterus. The infection affects the kidney’s ability to retain fluid, leading to your dog peeing a lot more often than usual. The increase in urination will lead to more drinking. If you notice your unspayed female dog is drinking excessively, has pus from the vulva, and is lethargic you should seek emergency veterinary treatment.

How to Test for the Cause of Polydipsia in Your Dog

There is no home test to determine the cause of polydipsia in your dog. There are a myriad of reasons for excessive thirst, and the above list is not exhaustive. The most important thing to do is note any uncommon signs—in addition to an increase in urination and drinking—so you can bring this information to your vet. You can also measure your dog’s water intake over 24 hours, and your vet may request a fresh urine sample.

Your vet will most likely start with a full head-to-toe clinical examination. Next, they may perform diagnostic tests, such as a urinalysis, full blood count, ultrasound and radiographs. These tests, along with taking a detailed history, will help the veterinarian find the underlying cause and propose medications or treatments.

Conclusion

Dogs need to consume water to stay hydrated, and should be given free and unfettered access to fresh drinking water at all times. Ideally, you should monitor how much water your dog is drinking, so you can pick up any changes quickly and know when they are drinking too much or too little.

Water consumption levels can be a good indication of health, and increased drinking may be caused by something as simple as elevated heat or exercise levels, but it can also be a sign of something more serious.

Featured Image Credit: Soho A Studio, Shutterstock