Dehydration in Cats & Dogs

Written by Small Door's medical experts

Dehydration is a serious concern for both us and our pets, particularly during the summer months. If your pet doesn’t take in enough water on a warm day, dehydration may come on quickly, so it’s important to know the signs, how to treat it and when to call the vet. Read on for all this, and tips on how to keep your pet well hydrated.

In This Article

What is dehydration in cats and dogs?

Dehydration is a condition that can affect both cats and dogs, and it occurs when more fluid is lost from the body than is taken in. It can be dangerous and even fatal if left untreated.

What causes dehydration in cats and dogs?

Dehydration can occur as a result of vomiting, diarrhea, overexertion or heatstroke, or it may be caused by an underlying disease such as kidney disease or diabetes.

Lack of water intake on a hot day can easily result in dehydration, so it’s important to ensure that your pet always has access to fresh, cool water. Additionally, you should take measures to limit their time and activity in the heat, and always provide them with a cool, shaded place to rest.

It’s also important to note that dogs can still get overheated and dehydrated even if they’re playing or swimming in water. All activities should be carefully monitored to keep your pet safe.

Are certain cats and dogs prone to dehydration?

Although any cat or dog can become dehydrated, there are specific pets that are more prone than others. This includes toy breeds such as Chihuahuas, Pomeranians, and Yorkshire Terriers as well as very young puppies and kittens. Additionally, any cat or dog that is older or nursing a litter is more prone to dehydration. Dogs or cats with kidney disease, diabetes, and certain types of cancer are also at a higher risk of getting dehydrated.

What are the signs & symptoms of dehydration in cats & dogs?

The signs of dehydration in cats and dogs can vary, depending on how dehydrated they are and the underlying cause of the dehydration. Common symptoms may include:

  • Loss of appetite

  • Lethargy and/or weakness

  • Vomiting and/or diarrhea

  • Dark colored urine

  • Excessive panting

  • Sunken eyes

  • Very pale or bright red gums

If you’re concerned your dog or cat may be dehydrated, there are a few techniques you can use at home to check your pet’s hydration status.

Checking their gums: Begin by lifting up your pet’s lip to observe their gums. Normally, pets’ gums are a light pink color and are slightly moist. Touch their gums with your index finger just above the tooth line. If they feel dry or ‘tacky’, and/or they look very pale or bright red, your pet may be dehydrated.

The ‘Skin Tent’ test: Gently grasp a pinch of your pet’s skin between their shoulder blades, pull it up slightly and then let it go. If your pet is well hydrated, the skin should quickly return to its normal position. In dehydrated animals, however, this response will be delayed and the skin will stay in the ‘tented’ position for longer. It’s worth noting that this is not a good test for overweight animals, as they may not show skin ‘tenting’ even when dehydrated, as the excess fat under the skin helps it return to place faster.

If you’re worried that your pet isn’t drinking enough but they have none of the signs of dehydration mentioned above, they may well be fine. Wet food has a high water content, so they may be receiving a lot of their daily water from their diet. If however, you are concerned about water intake, or your pet suddenly stops drinking as much as usual, it’s best to speak to your vet for advice.

If my dog has a dry nose, does that mean they’re dehydrated?

Many of us have heard the saying “a healthy dog has a wet nose”, and although a wet nose is a good sign, you don’t necessarily need to worry if your dog’s nose is a little dry. Although a dry nose can be a sign of dehydration, you don’t necessarily need to worry about it unless it’s accompanied by other symptoms of dehydration mentioned above.

Your dog may have a dry nose for several other reasons. The most likely reason your pet’s nose is dry is due to environmental causes (i.e. being in a dry environment from air conditioning or central heating). If a dry nose is accompanied with nasal crusting, this can indicate underlying problems and you should speak to your vet for advice.

How do I know if my pet is drinking enough water?

The amount of water an individual pet needs each day can vary greatly depending on their weight, activity levels, diet, the environment/weather, and whether they have any pre-existing medical conditions. Also, some pets will simply just like to drink more than others, and typically, cats tend to drink less water than dogs.

As mentioned above, if your pet is taking in fluids from other sources (wet food or high-water content treats such as ice cubes or melon), they may drink less than usual, and conversely, on a hot or high-exertion day, they will need to drink more.

In general, pets will usually drink when they need to, and you don’t need to worry that your pet isn’t getting enough water unless you notice any of the symptoms of dehydration mentioned above. If you suddenly notice a big change in the amount your pet is drinking, or any differences in their urinary habits that you can’t easily explain, speak to your vet for advice.

There are a number of medical reasons other than dehydration that can cause changes in fluid intake and urination, so it’s best to get your pet checked out in this case.

The best way to prevent dehydration is to ensure your pet has access to fresh water at all times, wherever they are, and to limit their time and activity in the heat.

How to treat dehydration in cats & dogs at home

If you’re worried your pet may be mildly dehydrated, there are a number of things you can do to help them at home. Firstly, remove them from hot environments and ensure they have somewhere cool and shaded to rest, with fresh water nearby. A cool room with air conditioning or a fan is ideal. Many mildly dehydrated pets will naturally drink water when it is available to them.

You can also try giving your pet a frozen treat (as long as they are not suffering from heatstroke) or food with a high water content, such as ice cubes, pupsicles, watermelon or cucumber. Ensure the seeds and rind are removed if providing any type of melon.

If your vet says it’s ok for your pet, you could consider providing a rehydration aid such as Pedialyte pops or fluid. Pedialyte is preferable to other sports drinks as the sugar content is low. However, it’s very important to never provide sugar-free varieties, as these may contain xylitol, which is toxic for pets.

When to see a vet for dehydration in cats & dogs

If your pet seems only mildly dehydrated (panting, tired) but drinks water when offered, it’s likely safe to monitor them at home and use the treatments mentioned above.

If they are presenting any of the more severe symptoms mentioned above, seem to be in pain, have not eaten or are experiencing vomiting and/or diarrhea for 24 hours, you should seek veterinary attention immediately.

If your pet is severely dehydrated, they will require IV fluids and supportive care ASAP to help re-establish a safe hydration level.

How long does it take a dog or cat to recover from dehydration?

A dog or cat suffering from mild dehydration will recover quickly after they have replenished the lost fluid. A pet with severe dehydration will take longer to recover, and their recovery time will depend on the extent of their dehydration and the underlying cause.

If the dehydration was caught early and your pet only requires IV fluids, they may only need to stay in hospital for a day. If however, the dehydration was severe and caused damage to any internal organs, additional treatment may be required and the recovery period will be longer and more complex.

How to prevent dehydration in cats & dogs

There are a number of ways you can help your pet to maintain an adequate water intake and avoid dehydration.

  • Provide fresh, clean drinking water: Ensure your pet has access to fresh water at all times, wherever they are. Ideally, the water supply should be changed twice daily and both the food and water bowls thoroughly cleaned once a day to prevent slime and bacteria from accumulating. Placing the bowls out of direct sunlight will also help decrease the speed at which bacteria can grow. Water fountains also need to be cleaned regularly for the same reason and manufacturers’ guidelines should be followed.

  • Multiple water bowls: If you have more than one pet, consider multiple water bowls so that each pet can have their own. Also, if your pet is particularly young, elderly or has joint issues, consider placing water bowls at different locations in your house to ensure they always have close access to water. This is particularly important for multi-level homes.

  • Consider a water fountain: Water fountains can be a great tool to encourage cats that prefer fresh or flowing water to drink more.

  • Add water to food: Soaking dry kibble in some warm water is also a good strategy to increase your dog’s daily water intake.

  • Take water on the go: For longer walks, on hot days, or if your pet is going for a swim, you should always carry a supply of water with you. There are many great portable options on the market – some of our favorites are the OllyDog Ollybottle, the Highwave Autodogmug and the Slurpy Sipper.

  • Mix it up: To encourage your dog to drink more on active days when it is hot out, you can add some unsweetened coconut water to their water (50:50) for some added electrolytes. Frozen treats like ice cubes, frozen (sodium-free) broth, and high-water foods like watermelon can also help.

  • Moderate activity levels on hot days: Dehydration can quickly occur on hot days, even if you don’t think your pet has been particularly active. Try to avoid going out at the hottest times of the day and limit your pet’s activity levels (excitable pets won’t stop playing even when dehydrated!)

  • Manage vomiting and diarrhea: If your pet is suffering from mild vomiting or diarrhea (i.e. they’ve experienced it a few times but otherwise seem bright and like their usual self), you should withhold food for the next few hours to allow their stomach to settle. However, water is fine during this time. If they continue to vomit/experience diarrhea or they show any concerning signs (such as lethargy, weakness), you should take them to be evaluated by a vet.

  • Manage chronic health conditions: When it comes to dehydration due to chronic health conditions, the best means of prevention is to provide any medication or other treatment according to your pet’s treatment plan, and to carefully monitor them for symptoms. Your vet can help to advise on any specific measures to take to keep your pet safe and healthy.

Keeping your pet safe from dehydration

Dehydration can occur relatively quickly on a hot day, particularly if your pet is excitable or engaging in long or strenuous exercise. By knowing the signs of dehydration, limiting your pet’s time and activity in the heat, and ensuring they always have a plentiful supply of fresh, clean drinking water, you can help to keep them safe from dehydration.

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What To Do

What To Do if Your Pet is Overheating

With summer around the corner, it’s easy for your pet to become overheated on a hot or warm day. They are wearing fur coats, after all! It’s important to look out for signs of overheating and learn what to do if you suspect heatstroke.

Get tips and tricks to keep your pet healthy

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