Noticing increased thirst in dogs can be concerning for many dog parents. It is easy to wonder if this is just a variation of normal or a sign something is wrong. To help answer those questions, integrative veterinarian Dr. Julie Buzby explains how to know if your dog is drinking too much water and discusses five common causes of increased thirst.
Do you ever have days where even the smallest of tasks—like filling a dog’s water bowl—seem like a lot of work? You have to bend down to pick it up, walk over to the sink and wait forever for it be full. Then you must carefully walk the bowl back to where it belongs and set it down without sloshing too much water on the floor. If you have multiple dogs, it may seem like you spend half the day filling dog dishes.
The effort involved in the task of filling a water bowl became very apparent to one of my clients and dear friends a few months ago. She brought her sweet, senior Labrador Retriever named Felmon to see me for an exam because he was drinking about three times as much as usual. Felmon’s mom remarked that she couldn’t believe how much he was drinking and how often she had to let him outside to go to the bathroom.
She had already thought through some of the possible causes. It wasn’t summer time, so she didn’t think it was related to heat or temperature. And he hadn’t gotten any salty treats. Poor Felmon’s mom was very worried about what could be going on with him. I told her increased thirst could be a sign of many issues. To get to the bottom of it, I recommended some lab work to screen for the most common culprits.
What constitutes increased thirst in dogs?
Felmon’s mom had done a good job of qualifying that he was drinking about three times more than normal. But this brings up the question of how much water a dog should normally drink.
On average, most dogs need about one ounce of water per pound of body weight per day. Or, a little over one cup of water per 10 pounds of body weight every day.
Therefore, a 40-pound dog needs 40 ounces, or approximately 4 to 5 cups of water every day. Whereas, a 10-pound dog needs about 10 ounces, or approximately 1 to 2 cups, of water every day.
On some occasions, dogs may drink a little more or a little less than this average amount of water. For example, take a dog who just came back from running a few miles with you. It would be completely normal for him or her to drink extra water when you get home. And you will probably be drinking more water too.
On the other hand, consider a dog who was been snuggling on the couch with you. He or she may not drink as much water right then. These small variations in water consumption are normal. Usually they aren’t a cause for concern.
It is also important to note that normal water consumption can vary slightly from dog to dog. Some dogs may normally drink more than that one ounce per pound and others less than that amount. This is why can be helpful to establish about how much water your particular dog normally drinks. If you notice consistent and significant variations from that number that cannot be explained by diet, ambient temperature, exercise level, etc., this may indicate there is a bigger problem going on.
The terms polydipsia and polyuria
If your dog is regularly drinking more water than normal, he or she is showing increased thirst. The term for increased thirst is polydipsia. Remember, what goes in, must come out. So, when drinking increases, this typically increases urination too. Increased urination is called polyuria.
How do I know if my dog is too thirsty?
Depending on your lifestyle and the environment your dog lives in, it can be difficult to tell if your dog is drinking excessive amounts of water. One of the biggest things that will help you track your dog’s thirst levels is measuring how much water you are giving your dog every day. The easiest way to do that is to keep count of how many bowls of water you are filling up.
Some dogs may have water available free-choice through a large container like a gravity dish, water trough, or multiple dog bowls. In those cases, consider using one single bowl while you are monitoring your dog’s water intake.
Having multiple animals who share a dish can also make it a bit harder. You may need to temporarily separate your dogs to see who is actually drinking more water. Even if you can’t separate your dogs for a whole day, a few hours might be enough to monitor the water intake.
The other option would be to monitor how many times your dog goes to the bathroom. If your dog is urinating more than normal, it is likely that she or he is also drinking more water. This method is a bit less precise but still effective.
The most important thing to remember is that you do not want to limit your dog’s water intake. He or she should always have water available. If your dog is drinking more, his or her body needs it. Withholding water could lead to dehydration.
What else should I monitor if my dog has increased thirst?
If your dog is experiencing polydipsia, it is important to watch for other symptoms as well. When dogs have excessive thirst, it is usually because of an underlying condition. This can be especially true in our beloved senior dogs. Keep an eye out for these other symptoms that sometimes accompany increased thirst:
- Increased urination
- Straining to urinate
- Blood in urine
- Abnormal smell to urine
- Increased or decreased appetite
- Pot-bellied abdomen
- Lethargic dog
- Painful belly
- Dry, sticky-like gums
- Delayed skin tent
If you notice any of these symptoms and/or increased water consumption, promptly make an appointment with your vet. The sooner you figure out why your dog is drinking so much water the sooner your vet can start treatment.
Five causes of increased thirst in dogs
The list of potential causes of polydipsia is long, but I wanted to touch on five of the most common culprits. There are plenty of other conditions are not covered here. Please always consult with your veterinarian to reach a diagnosis.
Hot days, times of high activity levels, vomiting or diarrhea, and many other scenarios can all lead to dehydration. In all of those cases, it is very important that your dog has access to plenty of water. Dehydration can happen in any dog at any age. Just like in people, it can be very serious in dogs.
One way to assess for possible dehydration is to perform a skin tent test at home. This involves gently pinching and raising the skin between your dog’s shoulder blades. When you let go, the skin should “snap” back into place within two seconds or less. If the skin fold remains raised or goes back in place slowly, your dog may be dehydrated. You can practice this skin tent on the back of your own hand to get the hang of it before trying it on your dog.
If you suspect your dog is dehydrated at all, please call your veterinarian immediately. And remember to ensure he or she has clean, fresh water available at all times. For more details, check out this Veterinary Partner handout on first aid for dehydration in pets.
2. Urinary tract infection
Another reason your dog could be drinking more water is because he or she has a urinary tract infection (UTI in dogs). Urinary tract infections can be very painful for your dog and have the potential to become dangerous if left untreated. In addition to drinking extra water, you may notice your dog showing these other UTI signs:
- Frequent urination
- Urination of small volumes at a time
- Straining to urinate or difficulty urinating
- Bloody urine
- Foul smelling urine
- Having urinary accidents in the house
3. Kidney failure
The kidneys are a very important organ in your dog’s body. They help filter your dog’s blood to remove by-products or toxins. The kidneys also help regulate water and electrolyte balance in the body and produce urine. If the kidneys aren’t functioning properly, dogs need to drink more water to compensate. Kidney disease can lead to a cascade of other problems in dogs, especially senior dogs. This is why it is so important to monitor for signs of kidney disease.
With kidney disease, it is common to see increased thirst and urination. You also might notice signs such as:
- An arched back or discomfort when the belly is touched (i.e. abdominal pain)
- Loss of appetite
- Abnormal smelling breath
- High blood pressure (i.e. hypertension in dogs)
Kidney failure can happen suddenly (known as acute disease) or over a longer period of time (known as chronic kidney disease). Either type of kidney failure can be very serious and require consulting with your dog’s veterinarian.
4. Diabetes mellitus
This condition is caused by a decrease in insulin production or your dog’s body not responding appropriately to insulin. Insulin is necessary for sugar (also called glucose) to be taken into your dog’s cells and used as energy to help your dog’s organs function correctly. If there is not enough insulin or the body doesn’t respond to insulin well, then the blood sugar gets too high. This known as hyperglycemia.
Diabetes mellitus can happen in any dog, but it is more common in middle aged or senior dogs. It can be very serious if ignored and not managed appropriately. Thankfully, there are multiple signs you can monitor your dog for that will help you detect diabetes. These include:
- Increased thirst and urination
- Increased appetite
- “Sticky” urine (due to excess glucose in the urine)
- Lethargy or decreased energy
- Cataracts in dogs (i.e. opacity of the lens making the eye appear cloudy)
- Weight loss
As a side note, there is another condition called diabetes insipidus that can also cause increased thirst and increased urination. It is not the same as diabetes mellitus. In diabetes insipidus, the dog’s body isn’t making enough antidiuretics hormone (ADH) or the kidneys are not responding to ADH correctly.
Normally, ADH helps ensure that the kidneys concentrate the urine appropriately. However, dogs with diabetes insipidus are unable to concentrate (i.e. pull water out of) their urine. Thus, they lose large volumes of water in their urine and must drink excessively to keep up with that loss.
5. Cushing’s disease
Dogs who have hyperadrenocorticism (i.e. Cushing’s disease in dogs) also tend to drink more water and urinate more frequently. Cushing’s disease occurs when the adrenal glands produce too much of a steroid hormone known as cortisol. This hormone, cortisol, is necessary for helping to regulating many body functions including glucose levels, metabolism, and the immune system. However, too much of it is a bad thing.
Cushing’s may be caused by a tumor of the pituitary gland (i.e. small gland in the brain) which sends too many signals to the adrenal gland to make cortisol or an adrenal tumor which over produces cortisol.
In some cases, extended use of steroids such as prednisone for dogs can also lead to a form of Cushing’s disease called iatrogenic Cushing’s disease. (As a side note, it is fairly common to see increased thirst and urination in dogs taking prednisone but that doesn’t mean they have iatrogenic Cushing’s disease.) Thus, it is always important to carefully monitor your dog whenever he or she is taking steroids.
Cushing’s disease can cause multiple symptoms including:
- Increased thirst and increased urination
- Increased appetite
- Pot-bellied appearance
- Decreased energy
- Abnormal hair loss
- Heat intolerance
What can I expect at the veterinarian’s office?
As you can see, there are a variety of medical conditions that cause increased thirst and urination in dogs, and this isn’t even an exhaustive list. Prior to coming to the veterinary appointment, consider tracking not only your dog’s water consumption but also any other symptoms. This information can help guide the diagnostic process.
When you first arrive, your veterinarian will perform a nose-to-tail physical exam to look for any changes or abnormalities. Based on the exam and the history you provide, your vet will most likely recommend a few different tests to help determine the cause of excessive thirst.
One of the first tests that your veterinarian might request is a complete blood count (CBC) and biochemistry profile. These are both basic blood tests that vets often run to gather information on sick dogs. The CBC will look at your dog’s red and white blood cells and platelets. The red cells numbers will help indicate if your dog is anemic. Changes in the white blood cells numbers can indicate an infection is present or point to several other conditions. It is also helpful to know if your dog has an appropriate number of platelets for blood clotting.
The chemistry profile can offer a lot of information to your veterinarian. It will help assess if your dog’s kidneys and liver are working properly. This is important because both kidney disease and liver disease in dogs may affect a dog’s water consumption. There are also different markers on the chemistry profile that could indicate if your dog has diabetes mellitus, Cushing’s disease, or other conditions that may lead to increased thirst and urination.
Another test that your veterinarian will likely recommend is a urinalysis. This will analyze how well your dog’s kidneys are concentrating urine. It will also look for signs of blood or crystals in the urine which could be an indication of bladder stones or a UTI. A urinalysis can also detect abnormal levels of protein in the urine, which may be related to kidney disease. Plus, the presence of glucose in the urine could indicate diabetes mellitus.
Depending on the results of these tests and the condition(s) your veterinarian suspects, there are other more specific blood tests he or she may request as well. For example, if the results of the chemistry profile are suspicious for Cushing’s disease, your vet may want to run a confirmatory test such as an ACTH stimulation or low dose dexamethasone suppression test.
In addition to blood tests, your veterinarian may want to perform X-rays or an ultrasound. These tests would help look at your dog’s organs, including the kidneys, liver, spleen, and adrenal glands. Occasionally, your vet may also refer your dog to a specialist for specialized testing.
What is the treatment for increased thirst in dogs?
Once the veterinarian determines why your dog is drinking so much water, he or she will recommend a course of treatment specific to your dog’s condition. Treatment for the five common conditions mentioned in this article includes:
Depending on the degree of dehydration, your vet may hospitalize your dog on intravenous (IV) fluids or give your dog some subcutaneous (SQ) fluids (i.e. fluids under the skin) and then send your dog home. It is also important to address the underlying cause of the dehydration. This may include medications to decrease vomiting and diarrhea or treatment of whatever other condition lead to the dehydration.
Urinary tract infection
Typically a UTI is caused by bacteria so the treatment will involve a course of antibiotics. Your vet may also prescribe anti-inflammatory and pain medications if indicated. It may also be helpful to increase your dog’s water intake by adding water to the dry food, giving some canned food, and/or ensuring he or she always has fresh water available.
The exact treatment will depend on the degree of kidney failure and how your dog is doing. It will often involve IV fluids (for more severe cases) or SQ fluids (for more mild cases). Some dogs also benefit from a specially formulated diet, or medications to control phosphorus levels, decrease protein loss in the urine, or reduce nausea. If your dog’s appetite is poor, your vet might also recommend an appetite stimulant for dogs.
Most dogs who have diabetes mellitus will respond best to daily or twice daily insulin injections given at the same time as meals. This takes the place of the insulin your dog’s pancreas would normally release in response to eating. Your vet may also recommend specially formulated diets and weight loss for overweight dogs (find out if your dog is overweight by determining your dog’s body condition score).
There are several medications your vet may use to decrease cortisol levels in dogs who have Cushing’s disease. These include Lysodren (mitotane), Vetoryl (trilostane), or selegiline. Occasionally, surgery to remove an adrenal tumor may be an option, but it is a fairly risky procedure.
Many of the conditions that cause increased thirst (especially kidney failure, diabetes mellitus, and Cushing’s disease) will require periodic monitoring and follow-up with the veterinarian. Stay in close contact with your vet about any changes you notice in your dog’s behavior, symptoms, or water intake during the treatment period. Your vet is a great ally when it comes to helping your dog feel his or her best.
Back to Felmon
You may be wondering what happened to Felmon. Well, after multiple blood tests and ultrasounds, I diagnosed him with Cushing’s disease and started him on medication to help him feel better. While he still has some hard days, Felmon is happily living out his senior years! His owner monitors him very closely for any changes and updates me regularly about how he is feeling.
If you notice that your dog is drinking more water or having other symptoms, it is important to consult your veterinarian. Some causes of increased water intake can be life threatening and early treatment can make a big difference in the outcome for your dog.
To help your veterinarian, consider measuring your dog’s water intake prior to the appointment (if possible—but don’t delay an appointment just so you can do this). And in the meantime, ensure that your dog’s bowl is always full and he or she has lots of chances to go outside to urinate.
While noticing your dog is drinking water like crazy can be concerning, know that your veterinarian is here to help get to the bottom of the issue and figure out a treatment plan. Sometimes, such as in cases of severe kidney failure, water consumption tends to stay high. But even then, you and your vet can work together to give your dog the happiest, most comfortable life you can.
Often though, appropriate therapy will help your dog’s water consumption return to normal (or at least closer to normal). So don’t lose hope—chances are good you won’t always be constantly filling your dog’s water dish and taking him or her outside for bathroom breaks. It will get better.
Have you ever noticed increased thirst and urination in your dog? What was the cause?
Please comment below.