Subscribe to our newsletter for FREE pet updates
Thank you! Please check your inbox to confirm your subscription.
Sorry, something went wrong. Please try again.

How to Protect Your Dog From Dehydration

As loving dog owners, we want to keep our pets safe and healthy. Learn about the risks of dehydration, preventative strategies and how to spot the warning signs in your dog.

dehydration in dogs


  • Dehydration in dogs is a medical emergency, often caused by a preventable lack of drinking water; however, the condition can also be caused by a number of underlying disorders and diseases, the most common of which is fluid loss from the urinary or GI tract
  • The most important step in diagnosing dehydration is finding the underlying cause in cases where a lack of drinking water isn’t the culprit
  • Treating the condition can be as simple as carefully rehydrating a dog who’s been without water for too long, or quite challenging depending on the underlying disease process that is causing fluid loss

Most dogs show signs of dehydration after about 24 hours without water, which is not to say they can or should go that long without it. Your canine BFF should have 24/7/365 access to clean, fresh water. If he has a dry mouth or nose, is excessively panting, and/or has thick rather than liquid drool, he’s showing mild signs of dehydration and needs immediate access to a clean water source.

Dehydration Is a Medical Emergency

A healthy adult dog (excluding puppies, seniors, and sick dogs) can go without water no longer than 48 to 72 hours before signs of dangerous dehydration appear, including skin “tenting,” which is when you gently lift a bit of skin at the back of your pet’s neck, and it stays up like a tent. In a well-hydrated pet, the skin snaps right back. Other symptoms of dehydration include:

  • Loose or wrinkled skin
  • Rapid weight loss
  • Depression
  • Elevated heart rate
  • Vomiting
  • Excessive urination
  • Panting
  • Weak pulse quality/strength
  • Diarrhea
  • Lethargy
  • Excessive drooling
  • Sunken eyes
  • Lack of appetite
  • Weakness
  • Sticky, dry gums
  • Collapse

These are all warning signs that your dog’s body is decompensating due to dehydration, and you need to get him to your veterinarian or an emergency animal hospital right away. Dehydration throws off the balance of electrolytes, such as calcium, magnesium, sodium, and potassium, which can interfere with the normal function of the body’s organs and systems. If a dehydrated pet isn’t quickly rehydrated, death can occur very quickly.

In the car, place your dog in line with an A/C vent or a battery-operated fan to cool him down. According to veterinarian Dr. Debra Eldredge,1 writing for Whole Dog Journal, you should offer water and/or an emergency electrolyte solution such as unflavored Pedialyte on your way. She cites a study that found that dogs were likely to drink more if provided a commercial electrolyte solution like Pedialyte vs. regular water.2

Diagnosing Dehydration

Significant dehydration in and of itself can be pretty easy for a veterinarian to spot. Sadly, two very common and entirely preventable causes of dehydration in dogs are being left outside in hot weather, and an outdoor water dish that freezes over or remains empty for prolonged periods of time.

However, if a lack of water isn’t the culprit, since the condition goes hand-in-hand with many common canine ailments, we can reasonably assume that if a dog has been vomiting, has had diarrhea, or isn’t eating or drinking, he or she is most likely dehydrated.

The bigger challenge is to identify the underlying cause of the dehydration, because it’s almost always a symptom of some other disorder or disease. Any condition that inflames or irritates any region of the gastrointestinal (GI) tract, from the mouth to the rectum, can cause fluid loss and dehydration.

Examples include excessive drooling, panting, ulcers, a bacterial, viral or fungal infection, GI parasites, or an obstruction in the digestive tract. Vomiting and diarrhea, which can be caused by any number of problems, are primary causes of dehydration in dogs and cats. Other causes of fluid loss include:

  • Kidney disease
  • Burns or a large injury to the skin
  • Ingestion of a toxin such as ethylene glycol, which is found in antifreeze
  • Endocrine system diseases such as diabetes mellitus, diabetes insipidus, and Addison’s disease
  • Heat stroke

By far, the most common trigger for dehydration in domestic dogs and cats is fluid loss from the urinary and/or GI tract.

Diagnostic tests will include a complete blood count and serum biochemistry profile, packed cell volume (PCV), total plasma protein (TPP) tests, a urinalysis, and a fecal test to check for GI parasites.

The results of these tests will tell your veterinarian a great deal about your pet’s overall health and organ function and can point to the existence of dehydration. Increased packed cell volume and total plasma protein levels plus an abnormal result for urine specific gravity definitively point to moderate to severe dehydration.

Depending on the results of these initial diagnostic tests, additional tests may be required to identify the root cause your pet’s dehydration. These can include x-rays, ultrasound imaging, urine or fecal cultures, tests for toxin ingestion, tests to assess the function of the adrenal glands, and/or a barium study to evaluate the structures of the GI tract.

Very young and geriatric pets who lose their appetites or have even just a couple of episodes of vomiting or diarrhea can dehydrate very quickly and should be seen by a veterinarian right away.

A sudden decrease in body weight is an important clue that your pet has also suffered an acute loss of body water.

Treatment for Dehydration

The goals for treating dehydration in a pet are to replace the fluids that have been lost, correct any electrolyte abnormalities, and identify and resolve the underlying cause.

A moderately to severely dehydrated pet will need to be hospitalized and given intravenous (IV) fluids and an electrolyte solution slowly over 24 to 48 hours, depending on the level of dehydration. The fluid replacement rate is calculated based on the severity of the dehydration and the animal’s size, weight, overall health, and other factors.

Typically, these patients will also receive heart rate and blood pressure monitoring and other types of monitoring, including urine output and body weight.

Correcting dehydration is really as simple as administering fluids that include missing electrolytes back into the body to replace what has been lost. However, the challenge is to learn why your pet became dehydrated in the first place.

Preventing Dehydration in Your Pet

Dogs are designed to get much of the water their bodies need from the food they eat, so make sure you’re feeding a species-specific balanced diet that is naturally moisture dense. This does not include kibble, which has very low moisture content.

The average kibble has about 11% moisture. A dog’s evolutionary diet contains about 70%. If a kibble-consuming pet isn’t drinking the extra water needed for hydration, he can live in a constant state of low-grade dehydration.

Leave multiple bowls of clean filtered water in glass or 304 metal (corrosion-proof stainless-steel) bowls around the house to encourage your dog to drink. Replace the water several times a day for finicky animals.

“Your dog should have fresh water available all the time,” Eldredge explains. “Water is essential for many bodily functions, including making urine to remove toxic metabolic wastes. Water helps your dog to thermoregulate when he is hot by panting. Blood flow, nerve and muscle function, and electrolyte balance are all affected by hydration. No dog should ever go without water long enough to enter a state of dehydration.”3

If your pet doesn’t seem to be drinking enough from his bowl, try adding some bone broth to the water, or the juice from a can of sardines. I’ve also had good success adding an all-natural electrolyte tablet called Bioplasma Cell Salt to drinking water.

If your pet is throwing up or has diarrhea that doesn’t resolve in a day or so, it’s a good idea to call your vet. This is absolutely crucial in the case of very young pets, senior and geriatric animals, and pets who are chronically ill.

Most Recent