Published: 22nd June, 2026
Updated: 24th September, 2026
Water is essential for almost every part of your dog's body, from regulating body temperature and supporting circulation to digestion and normal organ function.
But how can you tell if your dog is actually getting enough?
Dehydration happens when your dog loses more fluid than they take in. It can happen after exercise, during hot weather, while travelling, or alongside vomiting, diarrhoea or illness. Dogs can also become dehydrated simply because they're not drinking enough water.
Knowing the early signs can help you recognise when your dog may need more fluids — and when it's time to contact your veterinarian.
How can you tell if your dog is dehydrated?
Common signs of dehydration in dogs include:
- Dry or sticky gums
- Reduced skin elasticity
- Excessive or unusual panting
- Lethargy or low energy
- Sunken-looking or dull eyes
- Reduced appetite
- Thick or sticky saliva
- Increased thirst
- Reduced urination
- Refusing water, particularly alongside other signs of illness
These signs can have other causes too, so they shouldn't be used to diagnose dehydration on their own.
If your dog is very weak, disoriented, repeatedly vomiting, unable to keep water down, or showing signs of significant dehydration, contact your veterinarian promptly.
What is dehydration in dogs?
Dehydration occurs when a dog's body loses more fluid than it replaces.
Dogs naturally lose water through urination, breathing, panting and normal bodily functions. Their fluid requirements can increase when they're exercising, spending time in warm weather, panting heavily, travelling or unwell.
Vomiting and diarrhoea can also cause dogs to lose both fluids and electrolytes, which can increase the risk of dehydration. Learn what to do if your dog has gastro or is vomiting.
10 signs your dog may be dehydrated
1. Dry or sticky gums
Healthy dog gums are generally moist and slippery.
If your dog's gums feel noticeably dry, tacky or sticky, this can be a sign of dehydration.
You can gently lift your dog's lip and look at their gums, provided they're comfortable with you doing so.
Dry gums are more useful as part of the overall picture rather than as a standalone diagnosis.
2. Skin that doesn't spring back normally
One commonly used at-home check is the skin-pinch or "skin tent" test.
Gently lift a small fold of loose skin over your dog's shoulders and release it.
In a well-hydrated dog, the skin will generally return to its normal position quickly. If it remains tented or returns more slowly, dehydration may be a possibility.
However, this test isn't perfect. Age, body condition and breed can affect skin elasticity, so it shouldn't be used on its own to determine whether your dog is dehydrated.
3. Excessive or unusual panting
Panting is a normal way for dogs to regulate their body temperature.
After exercise or in warm weather, dogs naturally pant more and can lose additional fluid.
However, unusually heavy or prolonged panting — especially when your dog isn't exercising or isn't in a warm environment — can be a reason to pay closer attention.
If panting is accompanied by weakness, disorientation, vomiting, difficulty breathing or other concerning signs, seek veterinary advice.
4. Lethargy or low energy
A dog who is dehydrated may appear tired, sluggish or less interested in their normal activities.
Of course, tiredness can have many causes, so consider what else is happening.
Has your dog been exercising more than usual? Have they been outside in the heat? Are they eating and drinking normally? Have they been vomiting or experiencing diarrhoea?
Looking at the whole picture is important.
5. Sunken-looking or dull eyes
More significant dehydration can cause a dog's eyes to appear sunken or dull.
This can indicate that dehydration is becoming more serious and should not be ignored, particularly when accompanied by other symptoms. Veterinary sources list sunken eyes among the physical signs associated with dehydration.
6. Reduced appetite
A dehydrated or unwell dog may lose interest in food.
Reduced appetite isn't specific to dehydration, but when it occurs alongside dry gums, lethargy, vomiting, diarrhoea or reduced drinking, it's worth paying attention to.
If your dog stops eating and drinking or seems unwell, contact your veterinarian.
7. Thick or sticky saliva
Normal saliva should generally be relatively thin and watery.
Thick, sticky or rope-like saliva can occur alongside dehydration, particularly when a dog's mouth and gums also feel dry or tacky.
8. Increased thirst
It might seem obvious, but some dogs will drink noticeably more when they're trying to replace lost fluids.
An increase in thirst can happen after exercise, in warm weather or with certain illnesses.
A sudden or persistent change in how much your dog drinks is worth discussing with your veterinarian, particularly if it's accompanied by changes in urination, appetite, weight or behaviour.
9. Reduced urination
Changes in your dog's normal urination can provide another clue that something is different.
A dehydrated dog may urinate less because their body is conserving fluid.
However, reduced urination can also have other causes, including urinary or kidney problems. If your dog is straining to urinate, unable to urinate, or has a significant change in urination, seek veterinary advice promptly.
10. Refusing water
This can be particularly concerning when your dog is already showing other signs of illness.
A dog who isn't drinking enough may become increasingly dehydrated, while a dog who is already unwell may not feel like drinking.
If your dog refuses water and is also vomiting, has diarrhoea, seems weak or lethargic, or cannot keep fluids down, don't rely on home hydration strategies alone. Contact your veterinarian.
How to check if your dog is dehydrated at home
If you're wondering "Is my dog dehydrated?", there are a couple of simple observations you can make at home.
Check their gums
If your dog is comfortable having their mouth handled, gently lift their lip and look at their gums.
Healthy gums are generally pink and moist.
Dry or tacky gums can be a sign of dehydration.
You can also gently press a finger against the gum and release it. The colour should normally return quickly. This is sometimes called a capillary refill check. However, gum colour and refill time can be affected by other medical conditions, so this isn't a diagnostic test.
Try the skin-tent check
Gently lift a small fold of skin over your dog's shoulders and release it.
If it returns quickly, that's reassuring. If the skin stays raised or returns slowly, dehydration may be present.
But remember: this test isn't foolproof.
Older dogs, very lean dogs and some breeds with naturally loose or less elastic skin can make the test harder to interpret.
Look at your dog's behaviour
Don't focus on one sign.
Think about your dog's:
- drinking
- eating
- energy levels
- panting
- urination
- gums
- recent exercise
- exposure to heat
- vomiting or diarrhoea
Changes across several of these areas are more meaningful than one isolated symptom.
What causes dehydration in dogs?
There are many possible causes of dehydration.
Not drinking enough water
Some dogs simply don't drink enough, particularly if their water bowl isn't fresh, they're travelling, their routine has changed or they're distracted by their surroundings.
Hot weather
Warm weather can increase fluid loss through panting.
This is particularly important in Australia, where dogs may spend time outdoors in high temperatures and humidity.
Exercise
Running, walking, hiking and other physical activity can increase your dog's fluid requirements, particularly in warm weather.
Vomiting or diarrhoea
Vomiting and diarrhoea can cause significant fluid loss and may also result in electrolyte losses. Persistent gastrointestinal symptoms can therefore increase the risk of dehydration.
Illness
Some illnesses can cause dehydration directly or make a dog less willing or able to drink.
If your dog is unwell and their drinking habits change, speak with your veterinarian.
Travel or changes in routine
Some dogs drink less when they're travelling, staying somewhere unfamiliar or experiencing a change to their normal routine.
Which dogs are more at risk of dehydration?
Any dog can become dehydrated, but it's particularly important to monitor dogs during periods of:
- hot weather
- increased exercise
- vomiting or diarrhoea
- illness
- travel
- reduced access to water
Puppies, senior dogs and dogs with underlying health conditions may also require closer monitoring.
Dehydration after exercise: what should you do?
After a walk, run or adventure, make sure your dog has access to fresh drinking water.
If you're heading out for a longer walk or spending time outdoors, take water with you rather than relying on finding a water source along the way.
During hot weather, consider exercising during cooler parts of the day and give your dog opportunities to rest and drink.
And remember that panting after exercise is normal. It's the combination of excessive or prolonged panting with other concerning signs that matters.
If your dog appears weak, confused, collapses, has difficulty breathing or shows signs of heatstroke, seek veterinary care immediately. Heatstroke can be life-threatening and requires prompt veterinary attention.
How much water should a dog drink each day?
Water requirements vary between dogs depending on factors such as body size, diet, activity, environment and health.
A commonly used general guide is around 50–60 mL of water per kilogram of body weight per day, although individual requirements can be higher or lower.
For example, a 10 kg dog might consume roughly 500–600 mL of water across a day, while a 25 kg dog might consume around 1.25–1.5 litres.
This includes water consumed from drinking as well as moisture obtained through food.
You can read our more detailed guide here:
How Much Water Should a Dog Drink Each Day?
If your dog regularly struggles to drink enough, learn more about how much water dogs should drink each day and what can influence their hydration needs.
If your dog's water consumption suddenly increases or decreases, it's worth speaking with your veterinarian rather than assuming it's simply a hydration issue.
How can I encourage my dog to drink more water?
If your dog isn't drinking as much as usual, there are a few simple things you can try:
Keep water fresh
Refresh your dog's water bowl regularly and make sure clean drinking water is always available.
Take water on walks
A portable water bottle or travel bowl can make it easier to offer water while you're out.
Try different bowls
Some dogs have preferences around the size, shape or material of their water bowl.
Add moisture to food
Adding appropriate amounts of water to your dog's food can be another simple way to increase fluid intake.
Make hydration part of the routine
Offering water after exercise, during warm weather and while travelling can help make drinking part of your dog's normal routine.
If your dog consistently refuses water or has suddenly changed their drinking habits, talk to your veterinarian.
Can dogs drink electrolyte supplements?
Dogs lose electrolytes as well as fluids in some situations, including heavy fluid loss through vomiting or diarrhoea.
However, electrolyte products aren't interchangeable. Human electrolyte products may contain ingredients or concentrations that aren't appropriate for dogs.
If your dog is dehydrated or unwell, veterinary advice should come first.
For healthy dogs, a product specifically formulated for dogs can be used as part of an everyday hydration routine when given according to its directions.
Sip & Wag is designed for everyday hydration and gut support — not to treat dehydration, heatstroke, vomiting, diarrhoea or illness.
How Sip & Wag supports everyday hydration
Hydration and digestion are closely connected, which is why keeping your dog's water intake consistent can be an important part of everyday gut health. Learn more about the link between hydration and digestion in dogs.
Hydration doesn't have to be something you only think about when your dog is thirsty.
Sip & Wag was created to make everyday hydration and gut support simple.
Our Hydration + Gut Support formula combines electrolytes including sodium, potassium and magnesium with prebiotic fibre, probiotics, L-glutamine and vitamins B9 and B12 in one daily serve.
It can be:
- dissolved in water and served as a drink
- poured over food
- sprinkled directly onto meals
The beef liver flavour also gives dogs another reason to enjoy their daily routine.
But it's important to know the difference between everyday support and veterinary treatment.
Sip & Wag is designed for healthy adult dogs as part of their regular routine. It isn't intended to diagnose, prevent or treat dehydration or illness.
If your dog is showing signs of significant dehydration or is unwell, speak with your veterinarian first.
When should I call the vet?
Contact your veterinarian promptly if your dog:
- cannot keep water down
- is repeatedly vomiting
- has persistent or severe diarrhoea
- refuses food and water
- appears unusually weak or lethargic
- seems disoriented
- has severely dry or tacky gums
- shows signs of significant dehydration
- has difficulty breathing
- collapses
- may have heatstroke
- has another concerning change in behaviour or health
If your dog is unable to keep water down, don't keep trying to manage dehydration at home indefinitely. Veterinary treatment may be needed to address fluid and electrolyte losses and the underlying cause.
Frequently asked questions
Can a dog be dehydrated but still have wet gums?
Yes. Hydration can't be reliably assessed using one sign alone. Gum moisture, skin elasticity, drinking, urination, energy levels and other symptoms should all be considered together.
If you're concerned about dehydration, speak with your veterinarian.
Does panting mean my dog is dehydrated?
Not necessarily.
Panting is a normal way for dogs to cool themselves, particularly after exercise or in warm weather.
However, excessive or prolonged panting can contribute to fluid loss and may occur alongside dehydration or overheating. If panting is unusual or accompanied by weakness, disorientation or other concerning symptoms, seek veterinary advice.
How can I tell if my dog is drinking enough?
There isn't one exact amount that's right for every dog.
Water requirements vary depending on body size, diet, activity, weather and health. Monitoring your dog's normal drinking habits can help you notice meaningful changes.
Can dogs become dehydrated overnight?
It's possible, particularly if a dog is unwell, has been vomiting or has diarrhoea, has limited access to water, or has another condition affecting fluid balance.
A healthy dog with normal access to fresh water would not typically become significantly dehydrated simply because they slept overnight.
Can I give my dog electrolytes?
Only use electrolyte products that are appropriate for dogs and follow the recommended directions.
If your dog is already dehydrated or unwell, veterinary advice should come first.
How do I get my dog to drink more water?
Start with the basics: provide fresh water, try different bowls if appropriate, take water on walks, add moisture to food and make drinking part of your dog's daily routine.
If your dog suddenly stops drinking, don't assume they're simply being fussy. A change in drinking behaviour can be associated with illness and should be discussed with your veterinarian if it persists or occurs with other symptoms.
Can dehydration cause digestive problems in dogs?
Hydration supports normal digestion and overall body function. Dehydration can also occur alongside gastrointestinal problems such as vomiting and diarrhoea, which can create a cycle of fluid loss.
If your dog has ongoing digestive symptoms, veterinary advice is important.
Is Sip & Wag suitable for dehydrated dogs?
Sip & Wag is designed for everyday hydration and gut support in healthy adult dogs. It isn't a treatment for dehydration.
If your dog is showing signs of significant dehydration, vomiting repeatedly, experiencing persistent diarrhoea or unable to keep water down, contact your veterinarian.
The takeaway
Knowing the signs of dehydration can help you notice when something has changed with your dog.
Dry or sticky gums, reduced skin elasticity, unusual panting, lethargy, thick saliva, reduced appetite and changes in drinking or urination can all be reasons to take a closer look.
But dehydration can have many causes, and home checks can't replace a veterinary examination.
The best approach is simple: keep fresh water available, monitor your dog's normal habits, take extra care during heat and exercise, and know when to ask your vet for help.
Because good hydration is an everyday habit — not something you should only think about when your dog is already unwell.
Sip. Wag. Repeat.
About the author
Amy Foord — Founder of Sip & Wag
Sip & Wag was inspired by Amy's dog, Ziggy, and her search for a simpler way to support everyday hydration, gut health and wellbeing.
After navigating years of health challenges with Ziggy, Amy became increasingly interested in the role that everyday hydration and nutrition can play in supporting a dog's overall wellbeing.
Sip & Wag combines electrolytes, prebiotics, probiotics and other nutrients in a simple daily formula designed for dogs.
Disclaimer
This article is intended for general educational purposes only and is not a substitute for veterinary advice. If you are concerned about your dog's hydration, health, diet or medical condition, contact your veterinarian.