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Why is my dog not eating but drinking a lot of water?

Why is my dog not eating but drinking a lot of water?

It’s odd when you notice your dog isn’t eating but starts to drink excess water. There could be more than one behind-the-scenes situation happening that could cause this. Only in a few cases is this cause for concern. In all cases, you want to keep an eye on it. Let’s see if we can discover why this is happening to your furry companion.

Why is my dog not eating but drinking a lot of water?

Dogs drink excess water for several reasons. One reason is that they might be stressed and drinking more to keep themselves cool and hydrated. Another has to do with changes in diet, such as those which happen during the holidays when we give our pets table scraps or new treats. They may also have something stuck in their teeth or throat, which can cause them to drool or cough excessively, leading to an increase in liquid intake as well as dehydration if left untreated.

There are more serious reasons why this could be.

Liver Disease

There are several different causes of liver disease in dogs, one of them being hepatitis. This disease is an inflammation or infection in the liver that usually happens due to viruses but can also be caused by parasites, leading to jaundice. Jaundice leads to a yellowing of the eyes, gums, and skin known as icterus. Dogs that suffer from this condition also drink more water and urinate more frequently than usual for their bodies to flush out excess bile (a substance produced by the liver).

Dental Disease

Dental disease occurs when plaque and tartar build-up on teeth, eventually leading to tooth decay. The bacteria from this build-up can get into the bloodstream and lead to other health issues such as kidney or liver failure. Signs that your dog may have dental disease include bad breath, gum infections, loose teeth, or bleeding gums. If you notice these symptoms with an increase in water intake, it’s best to take them in for a check-up. The dog is drinking extra water to try and flush out the infection. In these cases, the veterinarian may recommend a round of antibiotics to help your pup and recommend pulling some decayed teeth to stop the disease from reoccurring.

Diabetes Mellitus

Diabetes Mellitus affects the way an animal’s metabolism works. It’s caused by the animal being unable to produce insulin, which regulates glucose levels in the blood. This inability leads to issues with their digestive system, leading to excessive urination and thirstiness. You may also notice cloudy eyes and lethargy. 

When should I worry about my dog not eating?

Dogs can survive for five to seven days without food, but you should contact your vet after they’ve stopped eating for two to get a head-start on things. Your dog may be going through a phase where they are tired of what you’re feeding them.

One dog owner found that after a few years of eating the same brand of dog food, her older dog began turning his nose up at it. He would stretch out his meals, then would only force himself to eat a little at each meal, each time seeming to plead with his eyes to feed him something else. The owner’s hunch was confirmed when she tried to feed him cooked bits of hamburger and rice from the dinner table, which he eagerly ate. She went through the process of finding a different brand of dog food he preferred much better and resumed his regular eating habits.

If your dog doesn’t eat anything offered to it, then you should contact your vet as a matter of precaution. Dogs don’t eat due to displeasure, pain, or illness.

What to do about my dog not eating but drinking?

Try switching up the brand and type of food to see if they would prefer something different. Some dogs suffer food fatigue just like a human can. Try a canned version once in a while over dry food or try a completely different flavor. Some dog food brands periodically change their formulas and ingredients over the years, and your dog may not like the new blend. Try a higher quality food or one that your vet recommends.

If they are eating a little bit but not usually, try offering them cooked hamburger, carrot, and rice as a meal instead of dog food and see what happens. Alternately, you can try this with cooked chicken (but no chicken bones, please). If, after two days, the dog is still not eating and experiencing other symptoms such as sadness, lethargy, or it seems to be in pain or just “off,” contact your vet for assistance.

Why is my dog drinking a lot of water suddenly?

It depends on why they feel they need the extra water. The weather could be sweltering and humid, or perhaps you two just came back from an extra-long hike, and they aren’t used to that level of physical exercise. Outside of that, dogs drink extra water for many reasons, but it is only a concern if they also stop eating or exhibit other behaviors like vomiting along with it.

Sometimes your dog may have gotten into something they shouldn’t have eaten, and they need the extra water to flush out their system, or perhaps a decayed and rotting tooth is causing them to develop a slight cough. Maybe the dog is developing kennel cough (a dog’s version of a cold).

If you can, inspect their mouths for any untoward swelling, broken, or newly missing teeth. Your dog may have a gum issue, or there may be a bite or sting you didn’t know about that needs addressing.

Why is my dog not eating but drinking and vomiting?

If your dog isn’t eating but is drinking and vomiting, a few things could be happening. Their thirst satisfaction isn’t registering, which causes them to keep drinking uncontrollably. You want to contact the vet. They may have eaten an object or something dead like a mouse or a squirrel their system isn’t used to, and they are drinking water to try and flush out the toxin through vomiting.

Things like pancreatitis and kidney failure can also be causes.


Several things can cause pancreatitis in dogs, but it’s usually due to an infection or bacterial overgrowth. Pancreatitis can also have other causes, including trauma and toxins.

Pancreatitis is often characterized by abdominal pain that worsens when the dog eats or drinks water or food. The abdomen may feel full and bloated with gas, and fluid may accumulate in the abdominal cavity. There might be vomiting after eating even small amounts of food, diarrhea with mucus present, and fever. Your pet could also vomit blood if it is dehydrated because its pancreas will not produce enough digestive enzymes for the body to utilize the food they are eating. At this point, your dog must get veterinary attention immediately.

Kidney Failure

If a dog is suffering from kidney failure, it may also drink more water. Kidney disease is a chronic disease that impairs or slows the function of the kidneys. The result of this can cause a buildup of waste products in the body. Kidneys help to control blood pressure and manage electrolyte balance as well as remove waste from the body. When it’s damaged, this process doesn’t happen as well as it should, leading to other problems. Signs that your pet has kidney disease include lethargy, vomiting, diarrhea, frequent urination, and excessive drinking. It might be time for some blood tests to check the levels of essential minerals such as potassium and phosphorus, which are regulated by the kidneys.

If the vomiting and not eating don’t resolve within 48 hours, or if you see a sharp decline in your dog’s overall personality and behavior in a less amount of time, contact your vet asap. They will be able to ask you some diagnostic questions over the phone and can determine when you’ll need to bring your canine companion in for a visit.