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Louisa the vet on... What to know about heatstroke in pets

Written by Dr Louisa Lane
15th Jun 2022
6 mins read
The image shows vet Dr Louisa Lane smiling and cuddling a black Cocker Spaniel puppy. She's on a yellow background with "Q&A" written behind her.
To kick off our season of summer safety tips, veterinarian Dr Louisa Lane tells us all about heatstroke in pets. You can avoid heatstroke by keeping your dog and cat out of the heat and make sure they always have access to shady spaces and drinking water. Never leave your pet in a hot, poorly-ventilated space like a conservatory or a hot car. If you think your pet has heat stroke, move them into the shade and poor cool (not cold!) water on them. You must call your vet for advice.
When our pets overheat, and are unable to cool down, they can develop a life-threatening condition known as heat stroke.
We mostly recognise heat stroke in dogs (because we take them outside with us and exercise them), but other pets like cats and rabbits can also suffer from this condition too.

What is heat stroke?

Just like in humans, our pets have an optimal healthy body temperature. In dogs and cats, this is around 38°C.
If their temperature rises towards 40-41°C and over, this leads to a whole host of problems within the body manifesting as seizures to organ failure.
The warmer your pet becomes, and the longer they remain warm, the more (permanent) damage is done.
Unfortunately, heat stroke
a killer which is why early intervention and prevention are essential to keep your pet safe.
Insuring your pet gives you peace of mind so if they ever fall sick unexpectedly, such as heatstroke, you know their vet bills will be paid for.

What causes heat stroke in pets?

There are three main causes of heat stroke in pets. These are:
  • Exercising in the heat, especially more ‘at risk’ breeds.
  • Generally overheating in warm weather; by being outside in the heat or left in a poorly ventilated room.
  • Being kept in a hot car.

Overheating after exercise

Whilst we commonly see warmer weather in the summer months such as July, we know the UK likes to give us heatwaves at other times of the year too.
But it does not have to be a scorching hot day to cause heatstroke in our pets, especially when we are exercising them, (like playing fetch).
As pet owners we must remain responsible, sensible, and prioritise their safety over our wanting to spend time with them on warm days. Especially for at-risk breeds (which we will talk about below.)

Being kept in a hot car

We should all know by now, to never leave dogs in hot cars. And although being kept in a hot car can cause heat stroke, it is important to note it's not the only cause of heat stroke in pets.
Recent studies suggest that the most common causes of heat stroke is due to exercising your dogs in the heat.
A dog can overheat within 6 minutes of being exercised, and for some breeds this can literally just be a short stroll.
We do not see heatstroke commonly in cats, most likely due to the fact we rarely travel with them or exercise them. However, they can still suffer from heat stroke if they overheat.

Being kept in a hot, stuffy room

Your dog or cat can get heat stroke if they simply overheat in warm weather.
This may be because the pets are kept outside in the heat, or left in a poorly ventilated room in a house like a conservatory, caravan, or mobile kennel.

What does heat stroke look like in cats and dogs?

Initially we are looking for signs of heat stress rather than stroke. This is the initial over heating phase which we can reverse.
When a pet is suffering from heat stress we might see:
  • Panting at rest.
  • Lethargy and not wanting to exercise.
Cats rarely pant like dogs, so if you are seeing your cat pant, do contact your vet immediately.
As our pets get progressively warmer and their internal body temperature rises, we may start to see:
  • Salivation
  • Vomiting and diarrhoea
  • Incoordination (also known as ataxia.)
  • Seizures
  • Lack of consciousness
  • Dark red gums (or even very pale gums if they start to go into shock.)

What dogs and cats are more at risk of heat stroke?

Whilst any dog or cat can develop heat stroke, some pets are at higher risk of developing it than others.
Breeds with underlying health conditions such as obesity, heart disease, laryngeal paralysis, and brachycephalic obstructive airway disease are at a higher risk.
Large breeds of dog also carry a higher risk.
Interestingly Springer Spaniels and Golden Retrievers also are at a slightly increased risk.
Don’t forget that often the ground temperature can be excessive for dogs and can burn their pads. If you cannot leave the back of your hand on the pavement for a few seconds, it isn’t fair to walk your dogs outside.
As for cats, cats with pale skin and white fur are a risk of sunburn (which can cause skin cancer). Look out for pet safe sun cream to use on their nose and ears.

How is heatstroke in pets treated? Is there anything I can do at home to help them?

The initial treatment for heatstroke in any pet is aimed at slowly cooling your pet down and rehydrating them.
Get them somewhere shaded and pour lukewarm/cool water on them. Not cold, but cool. (Using cold water constricts their blood vessels making it harder for them to cool down).
If they will drink, offer them some water.
You can repeat pouring water onto them until you seek veterinary help
You do not need to place cold towel on them as this can trap heat and stop them from cooling down.
Call your vet immediately for their advice. In most cases its essential that you seek professional medical help as soon as you can because your pets need to be monitored over a few days due to their risk of organ failure, which manifests days later.
If caught early, the heat stress can be reversed with cooling and rehydration.
However, the longer your pet is left in the heat, and the longer they go without treatment, the worse the prognosis and outcome.

Why is keeping my pet in a car so dangerous on a hot day? Can I still travel in the car with my pet when it's warm?

It is unacceptable to leave any pet alone in a car on a warm day, even with the windows open in the shade (this doesn’t really make a difference.)
The inside of a car (especially a darker car) heats up exponentially and does not coincide with the outside ambient temperature. At 24°C, within 30 minutes the inside of a car can reach almost 45°C.
We have all come back to a car where we have struggled to sit on the seat or touch the steering wheel because its become too hot. Imagine what it is like to try and breathe in that heat!
If you absolutely do need to travel with your pet in a car, you must supervise them at all times, use air-con, make sure they have access to fresh water, and make multiple stops for fresh air.
Please reconsider your journey if your car does not have cooling faciltiies as you must account for long stops in traffic.

You said that exercise is the biggest cause of heat stroke in dogs. Should I still exercise my pet in warm weather?

Take into consideration your specific pet's health and be sensible about what exercise you do on warmer days.
Dogs die if they’re kept in hot cars and exercised in the heat. But they wont die if they do not get a decent walk for a few days.
If you need to exercise your pet, keep it calm, and do this early in the morning and later in the evening.
Whilst it can seem confusing, letting your dog swim on warmer days can also cause them to overheat.

Are there other ways to can prevent heatstroke in pets?

Heat stroke is extremely serious and is completely avoidable.
Whether you have a cat or a dog, the advice to prevent heat stroke in pets remains the same.
  • Always make sure they have access to multiple bowls of water.
  • Make sure they have access to shaded areas.
  • It is best to keep them indoors in a well-ventilated cool place.
  • Use cooling mats for them to sit on.
  • Keep them out of direct sun.
  • Do not place pets in poorly ventilated rooms like caravans and conservatories, as they can heat up like a greenhouse.

How can I keep my pet safe in hot weather?

Please be sensible with your pets. All pets need to be kept away from heat, kept somewhere cool and shaded, with access to water.
Always keep an eye on them and seek veterinary help immediately if you have concerns about your pet overheating.
It is far better and safer to keep them inside on a warm day than risk them developing heat stroke.
Veterinary treatment for your dog with heatstroke, especially if they require intensive care , fluid therapy, and repeat blood testing to monitor organ function, can rack up into the thousands of pounds.
Please make sure you take out pet insurance as soon as you can to take away the added pressure of financial worries when your pets are poorly.

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