Why Is My Dog Not Drinking Water and Lethargic?

Dog not drinking water and lethargic
A lethargic dog that is not drinking water is a real
worry ¹

There are many reasons why a dog won’t drink water and lie in his corner and some of them can indicate a serious health problem. Here is a look at the most common illnesses that can cause your dog’s sudden change of behavior.

Common Infections that Cause Lethargy in Dogs


Parvovirus is a disease caused by a virus that spreads easily from dog to dog through contact with their feces. The symptoms of the disease appear within 3-7 days and include lethargy, vomiting, fever, and diarrhea, which is often bloody. You should be careful if you notice these signs in your dog as parvo is deadly in 90% of the cases. Aggressive treatment, including antibiotics, can save your pet’s life if you contact a vet immediately. Also keep in mind that vomiting and diarrhea cause dehydration, which can be made even worse if the dog won’t drink water.

Kennel cough

Kennel cough is a respiratory disease easily recognizable by its distinctive dry, honking cough. This disease also causes vomiting, gagging, and fever, which might make a dog lethargic. It is a very contagious disease, but, fortunately, it usually clears up on its own. It can be dangerous to young puppies and animals with underlying health conditions.


Distemper sometimes called footpad disease, is a viral illness with a high mortality rate, although the outcome depends on the dog’s age, overall health, and the virulence of the virus strain that infected the animal. The main symptoms of canine distemper are high fever, eye inflammation, labored breathing, loss of appetite, and lethargy. There is no specific treatment for distemper, other than administering fluids and electrolytes to alleviate the symptoms, as well as antibiotics to prevent secondary bacterial infections. 

Heartworm disease

Heartworm disease is caused by a parasitic roundworm that spreads through mosquito bites. Despite its name, this virus first attacks the lungs and only migrates to the heart during the later stages of the disease.

It is a disease with a slow progression as it takes about six months from infection for the worms to mature. The symptoms only appear when the worms migrate to the heart and include weight loss, fainting, extreme tiredness even after mild exercise, making owners worry about why the dog is lethargic. The treatment lasts for several weeks during which the dog should not exercise at all to allow its body to safely eliminate the dead worms.


Leptospirosis is a bacterial disease that affects humans as well as several types of animals. In dogs, the disease causes fever, weakness, loss of appetite, and urinary symptoms. Leptospirosis can be treated with antibiotics. 

Metabolic and Organic Diseases

Congestive heart failure is a frequent health issue affecting the elderly, but dogs go through the same problems as they age. The symptoms become more noticeable as the condition worsens. Lack of oxygen will make the dog tire easily, so your pet will appear weak and lethargic. As the dog doesn’t exercise much at this age, his need for water decreases. The condition is not curable, but drugs can alleviate the symptoms and sustain heart function.

Diabetes is a condition that usually affects middle-aged dogs, and is more prevalent in female overweight dogs. Although diabetes first presents itself with excessive water consumption, in many cases owners won’t notice something’s wrong with their pet until the dog becomes weak and lethargic or when the dog goes blind, as the disease causes cataracts. 

However, with the right medication and dietary changes a dog can lead a pretty normal life and die of old age. 

Hypoglycemia is the opposite of diabetes, causing low blood sugar. It also causes weakness and seizures. 

Liver disease is another health issue causing symptoms like weakness, loss of appetite, and lethargy. Depending on the cause, the disease might require medical treatment, dietary changes, or even surgery. 

Other health conditions causing lethargy in dogs include tumors, anemia, trauma,

and pain. The might might also refuse to drink if he’s been poisoned or bitten by a snake.

Can Kidney Problems Make a Dog Stop Drinking Water?

Many pet owners assume the dog has a kidney problem when it becomes lethargic and refuses to drink water. However, this is not the case.

Kidney failure means the animal’s kidneys do not function properly anymore and this is generally caused by age and the inevitable wear and tear of internal organs. Kidneys are responsible for filtering toxins from the blood and when they start failing they go into overdrive. The dog will drink excessive amounts of water to make the kidneys work harder and this will cause a large urine output. Advanced kidney disease causes vomiting, loss of appetite, diarrhea, and bad breath. 

Caught early the disease can be managed with diuretics and other medications. 

Kidney infections in dogs are usually caused by bacteria which can affect only the bladder or reach the kidneys, causing pyelonephritis. This latter is characterized by excessive thirst, making the dog drink more water, not less. This also determines frequent urination. Other possible symptoms are pain in the sides, fever, vomiting, and loss of appetite. Left untreated some kidney infections can lead to kidney failure.  

Other Reasons a Dog Won’t Drink Water

While the owner worries his beloved pet might be sick, there are other non-medical reasons causing the dog to refuse water.

The dog lacks exercise – This happens particularly in cold weather when the dog doesn’t go out much and doesn’t exercise enough. The dog doesn’t need much water during periods of inactivity, hence you have no reason to worry unless this has been going on for days and the dog drinks even less.

Aging also makes a dog exercise less, hence the reduced need for water. In both cases beware of dehydration.

Change of place, change of water

If you’re out of town with your pet, his refusal to drink water might be caused by the fact it tastes or smells different than the water at home. You might not notice a

difference, but a dog will. Try giving the dog bottled water and next time remember to bring along a bottle or two of water from home.

Negative experiences

Sometimes the reason might be purely psychological. Maybe something happened to your dog while he was drinking water – like someone stepping on his paw or a bee sting and he is afraid it might happen again. Try putting his water bowl in a different place or even change it to erase bad memories.

How Much Water Does a Dog Need?

The quantity of water a dog needs per day depends on the weather and how much exercise your pet does that day. Also, some dogs might pee more than others and require more water consequently.

As a rule, a dog needs about one ounce of water for every pound of body weight per day. This means that a 50 pounds dog will need 50 ounces of water.

Dehydration in dogs

Many diseases can cause dehydration in dogs, but so does vigorous exercise on a hot summer day. Here are the main signs your dog might be dehydrated:

Dry mouth and nose

Sunken eyes

Skin that has lost elasticity

Rapid heart rate

Weak pulse



If you’re not very sure what’s wrong with your dog, but suspect dehydration you can perform a quick skin test:

Gently pinch the skin between your dog’s shoulders between your fingers and try to lift it an inch or two. Under normal circumstances, the skin should go back immediately when you release it. But, in dehydrated dogs the lack of water makes the skin lose elasticity so the skin will take a longer time to retract or, in severe cases, won’t retract at all. Try to give your dog some water ASAP and contact a vet

in the meantime as your pet will need rehydration fluids.

What to Do when the Dog Won’t Drink Water

When a dog persistently refuses water, that’s cause for alarm. If you don’t see other worrying signs that might indicate a serious problem try some simple remedies.

Change the position of the water bowl, clean it thoroughly, or change it altogether. 

Try to make the water more appealing by mixing in a little meat broth. Alternatively, you can put some fruit juice in his water, strawberry, and apple in particular.

Try giving your dog cold water or see if he wants to lick some ice cubes.

Switch to wet food for your dog and add a little water to that too.

Soak one of his toys in water to make the dog get some water when he chews on it. You can also try putting the soaked toy in the freezer to make it more interesting to the dog.

Some dogs prefer running water so see if your dog is tempted to drink from a faucet in the garden. Consider buying a water fountain for your dog.

When you’re trying to re-hydrate your dog, don’t offer large quantities, try giving him a few sips every five minutes.

Add unflavored Pedialyte to his drinking water to combat electrolyte imbalances.  

In case of emergency, don’t wait till your vet appointment and try to force some water down his throat. You can use a plastic syringe or a turkey baster to squirt some cool fresh water into his mouth. Try aiming for the cheeks, not down his throat directly to avoid choking.

Never Ignore a Dog who Won’t Drink Water

When your dog won’t drink water and seems lethargic, you should keep an eye on him and try to tempt him into accepting a few sips. Try the remedies listed above. It could be something temporary caused by some pain or maybe the water tastes funny. However, if the situation persists take action to prevent dehydration and go see a vet. There might be something seriously wrong with your dog.

Photo Credits

¹ Photo by Engin Akyurt from Pexels

Sarah Pulsen

Hello, I have been in love with dogs since I was a little girl. I became even more infatuated with them when I was told by my Mum that I couldn't own one. Since I left home there has rarely been a time in my life when I have lived without a dog. My current dog is a Collie Terrier cross, called Ian.