Dehydration happens when your dog doesn't drink enough fluid to make up for what their body is losing. Untreated dehydration can be life threatening. Dogs of any breed or sex may become dehydrated, but puppies, older dogs and toy breeds are most at risk.

Dogs become dehydrated when the amount of fluid they take into their body is less than the amount they lose in urine, faeces (poo), panting and vomit (sickness). Mild dehydration is easily corrected when your dog drinks more. But dehydration can also be a symptom and a cause of serious illness. If left untreated, severe dehydration leads to organ damage and eventually organ failure. Talk to a vet as soon as possible if your dog refuses to eat or drink and/or is unable to keep fluids down.

What to do if your dog is dehydrated

• Keep your dog cool and comfortable; check they have enough fresh, clean drinking water

• Offer small frequent drinks of water to prevent gulping

• Check if your dog is still passing urine; monitor how much

• Check for severe dehydration: dry gums, sunken eyes, dry nose, panting, extreme tiredness, skin that doesn't spring back when you lift a fold

Severe dehydration needs urgent veterinary treatment. Call a vet without delay if your dog is severely dehydrated.

Common causes of dehydration in dogs

Dogs become dehydrated either because they are losing excessive fluid or aren’t consuming enough to meet their needs. Often, it’s a combination of both.

Increased losses:

• Severe vomiting or diarrhoea

• Polyuria: urinating (peeing) much more than normal. Chronic kidney disease, Cushing’s disease (hyperadrenocorticism), diabetes, salt water poisoning (sea water) can all be causes of this.

• Excessive panting: caused by fever, hot rooms or hot weather or extreme exercise.

Reduced intake:

• Water deprivation: missing, empty, insufficient or inaccessible water bowls

• Physical inability to reach water: caused by pain, weakness or uncoordination

• Anorexia: refusing food and water

Illnesses frequently associated with dehydration include gastroenteritis, heat stroke, chronic kidney disease, diabetes, poisoning, beach diarrhoea.

When to worry if your dog is dehydrated

Call your nearest vet if your dog:

• Has vomiting or diarrhoea and is unable to keep any fluids down

• Has not passed any urine for 24 hours

• Is showing signs of severe dehydration

• Is struggling to stand, wobbly or collapsed and hard to rouse

Tips to prevent your dog becoming dehydrated

• Make sure your dog has easy access to fresh, clean drinking water at all times.

• Keep your dog cool and avoid exercising in hot weather. Opt for early morning and evening walks when it’s cooler.

• Take fresh drinking water on long walks, trips to the beach or car journeys.

• Never leave your dog in a hot car.

• Keep up-to-date with vaccinations and regular anti parasite treatment to prevent preventable causes of vomiting, diarrhoea and serious illnesses.

How to tell if your dog is dehydrated

Ways to check if your dog is dehydrated:

• Check their gums: In dehydration, they are dry and sticky instead of moist. They may also be pale or dark red colour instead of salmon pink.

• Test for a skin tent: Pinch and lift a small fold of skin on their neck or forehead. In dehydrated dogs, the skin stays raised like a tent instead of springing back into place.

Signs to look for:

• Dry nose and sunken eyes

• Excessive panting; fast heart rate

• Lack of energy or sleeping more

• Passing less or no urine; dark concentrated urine (except dogs with chronic kidney disease)

• Weakness, unsteadiness, and difficulty getting up

• Collapse and coma

Caring for dehydrated dogs at home - and when not to!

Mild dehydration

• Ensure their water bowl is topped up regularly. Encourage them to take small frequent drinks rather than gulping a lot at once.

• Offer ice cubes to dogs to tempt dogs who won't drink from the bowl.

• Offer wet food. Add water or salt free stock to food if your dog’s still eating.

Moderate dehydration

• Offer an electrolyte replacement solution to replace fluid, sugar and salts. To make an electrolyte replacement solution at home, dissolve 1 teaspoon of household salt and 2 teaspoons of sugar in 500mls of boiled cooled drinking water.

• Offer small amounts of water or electrolyte solution every hour. Spoon fluids slowly into the mouth, taking care to avoid choking.

Call a vet if your dog does not recover fully within 24 hours

Severe dehydration

Signs of this include dry gums, sunken eyes, panting, extreme tiredness, and skin that doesn't spring back when you lift a fold. Severe dehydration can lead to organ damage and death. It needs prompt and aggressive vet treatment. Call a vet without delay if your dog is severely dehydrated.

Vet Treatment for dehydration in dogs

Emergency treatment for severe dehydration:

• Hospitalisation and monitoring

• Giving fluids directly into a vein in your dog's leg

• Sometimes giving fluids under the skin. This may be recommended for less urgent cases, young puppies and where injecting into a vein isn’t possible; occasionally continued at home by owners under vet guidance.

Are some dogs at more risk of dehydration?

Although any dog, of any breed, age or size, can become dehydrated under certain conditions, some dogs are at greater risk.

• Age groups: Young puppies and older dogs

• Certain breeds: Toy breeds, brachycephalic (short-faced) breeds

• Dogs with existing illnesses; such as kidney disease, diabetes, heart disease.