What happens when a dog becomes dehydrated?

Severely dehydrated dogs need immediate emergency veterinary care. If your dog shows signs of shock, heatstroke, or severe dehydration, call your vet or the nearest pet emergency hospital right away so that your dog can be examined, and necessary, life-saving treatment can be given. Symptoms include vomiting and/or diarrhea, less energy, weakness, or difficulty standing.

Like us, dogs will gain and lose water throughout the day. They lose water by panting, breathing, urinating, defecating, and evaporation through their paws. They balance the loss of water by eating and drinking.

When dogs lose more water than they take in, they become dehydrated, decreasing body fluids and blood flow. This decreases the amount of oxygen organs and tissues receive. Dehydration also leads to a loss of electrolytes including sodium, chloride, and potassium which have important functions in the body. Electrolytes contribute to the following:

• Balancing the body’s pH
• Help to move nutrition into cells
• Allow for normal muscle function
• Regulate nerve function

Vomiting and diarrhea, for example, often cause a loss of electrolytes, while dogs with heatstroke or heat exhaustion often have higher than normal levels of these electrolytes. If left untreated, dehydration can result in kidney and other organ failure and death.

How much water is normal for my dog to drink?

In general, healthy dogs need about an ounce of water per pound of body weight per day. If they are experiencing fluid losses, such as vomiting or diarrhea, their water intake should increase to keep up with these demands.

Symptoms of Dehydration in Dogs

Symptoms of dehydration can be seen with as little as a 5% loss of fluid from the body. If your dog is dehydrated, you might notice some of the following signs:

• Decreased activity, weakness, difficulty standing
• Eyes appear sunken
• Dry nose
• Dry, sticky gums
• Thick saliva
• Decreased elasticity of the skin
• Loss of appetite
• Vomiting
• Decreased energy
• panting
• Shivering
• Unconsciousness
• In extreme cases, death

How to Check for Dehydration in Your Dog

1. Gently pinch your dog’s skin between their shoulders, lifting the skin about an inch or two from the body. When releasing the skin, it should normally return to its place right away. When dogs are dehydrated, the skin will slowly return to place or remain lifted, just as you pinched it.
2. Check your dog’s gums for capillary refill time (the amount of time it takes for the color to return to the gums once you press) by lifting your dog’s lip, checking the gum color (which should be the same color pink as underneath your fingernail). Press on the gum with your index finger until it turns white. Release your finger and see how quickly the color returns to the gum. The gums of a hydrated dog will return to normal color right away, while the gums of a dehydrated dog will be slower taking up to 3 seconds for the color to return.

Causes of Dehydration in Dogs

Dogs can quickly become dehydrated from continued vomiting and/or diarrhea, being active in extremely hot weather, or from being sick with a fever. Dogs with diabetes can become dehydrated when they have too much sugar in their blood, causing them to urinate a lot. Increased panting, which is how dogs manage their body temperature when they get too hot, can also lead to dehydration.

Severe dehydration, left untreated, can lead to severe conditions including kidney failure, abnormal heart rhythms, and even death. Dogs experiencing mild dehydration often recover quickly once they have taken in enough plain water.

When dogs become severely dehydrated, drinking water will often not be enough to rehydrate and stabilize their condition. Often, if they have signs of vomiting or diarrhea, continuing to offer water will stimulate them to continue to vomit which further dehydrates them, making their condition worse. Your vet will determine what’s causing the dehydration and give any necessary medication along with fluid therapy to relieve your dog’s symptoms and help them recover.

What to Do if Your Dog is Dehydrated

You want to help your dog and relieve their symptoms, but in some cases, home remedies (such as Pedialyte) that delay veterinary care, can actually worsen the symptoms. You can offer a mildly dehydrated dog small sips of water or pieces of ice to lick, every few minutes. Too much water too quickly could cause vomiting, making dehydration worse. Always contact your vet for recommendations if you suspect your dog is dehydrated.

Once your dog has been assessed by your vet, they will make recommendations for the best way to rehydrate. In mild cases, the vet may recommend Pedialyte or another electrolyte solution or rice water. Rice water helps, especially in cases of dogs experiencing frequent diarrhea as it helps firm loose stools. Always follow your vet’s recommendations regarding how much and how often to give these options to your dog.

For moderate dehydration, your vet may opt to treat the dehydration with fluid therapy under the skin, also known as subcutaneous fluids. The type of fluid used depends on your dog’s condition and diagnosis. It often has a blend of sterile water, dextrose (a type of sugar), and balanced electrolytes. When given under the skin, the fluid is absorbed slowly over several hours. For dogs with chronic conditions such as chronic kidney disease, owners can learn how to give fluid therapy subcutaneously at home.

Preventing Dehydration in Your Dog

Make sure your dog has access to clean, fresh water in several places around the house. If you will be gone from home for 6 to 8 plus hours, consider automatic water bowls and pet fountains and always offer your dog clean, fresh water with every meal.

Going to the dog park or for a ride? Bring a portable bowl and bottled water with you. After active play or exercise, offer small amounts of water to your dog. Allow him/her to drink a small amount then offer it again in a few minutes. Remember that if you’re outside in warm or hot weather and you get thirsty, your dog is probably thirsty too.

When to Contact a Vet

If your dog continues to vomit, has diarrhea, acts weak, or is not responsive to you, or shows other concerning symptoms, contact your vet right away. For an initial assessment, you can schedule an appointment with one of our vets using the FirstVet App.

Read more:

Can Dogs Get Sick From Drinking Too Much Water?

Everything You Need to Know About Diarrhea in Dogs

Everything You Need to Know About Diarrhea in Dogs

Need to speak with a veterinarian regarding your dog’s dehydration or another condition?

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