Heat Stroke, It’s a Hot Topic – Dr. Sophie Bell

Heat Stroke, It's a Hot Topic - written by Dr. Sophie Bell

Every year the social media pages explode with heat stroke tips and conflicting advice. Let’s explore heat stroke, which firstly should be renamed heat related illness, and bust some myths along the way.

As a vet I see heat related illness cases every year, almost every case is avoidable. When the weather hits 20°C and beyond problems start to arise. It takes weeks for an animal to climatise to hot weather, so when these weather extremes hit, we need to be prepared to protect our pets.

First up who is most at risk of suffering ill affects to life threatening symptoms from the heat?


Brachycephalic animals can suffer tremendously even at temperatures as low as 19°C. Their head shape makes it harder for cold air to exchange with hot air. For dogs this makes panting less effective. This is just one factor that can make keeping cool problematic and puts them in the high-risk group.

Giant breed dogs find cooling down very difficult, a volume to surface area problem which equally effects animals who are overweight or obese. With 2/3rds of our dogs deemed as overweight or obese in the UK, this puts a high number at risk.

Elderly animals also find cooling difficult, especially if they are suffering with heart and lung disorders. It is better not to subject these high-risk animals to temperatures above 20°C but also to be able to read the signs your pet is struggling as some will find the high teens far too hot.

Did you know?

The Chow Chow has 17x the risk of developing heat related illness compared with other dogs. With the English Bulldog coming a close second



How can we minimise the risk and prevent this life-threatening problem from occurring?

The key is prevention, recognition, immediate management, and veterinary intervention.



There are many ways to keep you pet cool! Here are a few suggestions…

  • Avoid walking in hot weather! Walk very early in the morning or late in the evening, or not at all if the temperature doesn’t allow. Provide fun games at home instead such as hiding treats (not too many!) provide some icy fruits like blueberries, raspberries, or watermelon to keep your pet entertained and cooled. NEVER give grapes.

Myth buster: It is fine for your dog to have frozen icy treats and pet ice cream during the hot weather! These will NOT send you pet into shock.

  • Place multiple water stations around the house, make sure it is kept fresh and cold. Hydration is extremely important.
  • Choose a cool room in the house for your pet to rest, close the curtains/blinds, and use a fan to keep the air flowing.
  • NEVER leave your dog in a room such as a conservatory as temperatures can soar quickly. And of course, NEVER leave your dog in a car for any period.
  • If you have outdoor space, provide a paddling pool for your pooch. Water play is great fun but avoid allowing your dog to play with hose water. This can lead to excess water ingestion and lead to a life-threatening condition known as hyponatraemia.

Be mindful: As a pet loving nation, we all want to protect our fur-families. Just remember some people do not have a garden space or have a dog who will only toilet away from the home. This means some people maybe forced to venture out a short distance in hot weather to allow their pet to toilet. We should ask the owner before making an instant judgement that they are putting their dog’s life at risk.


Heat related illness follows 3 stages, with heat stroke being the third and final life-threatening stage.

Stage 1: Heat stress
The symptoms:

  • Fast pulse
  • Heavy panting
  • Enlarged tongue
  • Red gums and tongue

Stage 2: Heat exhaustion
The symptoms:

Those seen in heat stress PLUS

  • Drooling when panting
  • Weak
  • Ataxia (wobbly) when moving
  • Vomiting (without blood)
  • Diarrhoea (without blood)

Stage 3: Heat stroke
The symptoms:

Those seen in heat stress and heat exhaustion PLUS

  • Seizures
  • Collapse
  • Bleeding – from the nose, and/or bruising on the skin
  • Vomiting blood
  • Diarrhoea with blood
  • Petechiae haemorrhages (small red spots) seen on the gums and skin

These animals with heat stroke will die if left untreated, and prognosis is guarded even with treatment.


Immediate management/first aid

It is important to recognise symptoms and begin active cooling immediately prior to seeing your vet. You can always communicate with your vet during this stage.

  • For those suffering with stage 1 and 2 use cold water from the cold tap on hairless areas such as the feet and legs, the belly and groin.

Myth buster: Cold water around 14°C is the advised temperature. Using tepid water is not enough and is now considered a myth! 14°C is the average water temperature straight from the cold tap.

  • Do NOT cover your pet with a towel, even if it is cold and wet. Heat needs to escape and covering them will stop this and serve to heat them up
  • Provide a fan to circulate cool air
  • Place cool packs (ice packs wrapped in a thin cloth) on the spine, groin, armpits, and abdomen. This is where major blood vessels run
  • Apply cold water to the inside of the ears
  • Cool steadily, no need to rush
  • Ideally, we stop cooling when the body temperature is 39.2°C

Warning!! Symptoms can progress, always speak to your vet even if your pet appears mildly affected or seems to be improving.

For stage 3, heat stroke, you need to be more aggressive with your cooling!

  • Icey cold water is required
  • Submerge the body, keep the head out of the water
  • Your vet may advise honey/jam on the gums as blood sugar levels drop
  • Heat stroke is heat shock, these animals are dying, there is no time
  • Cooling is rapid

Rapid cooling is NOT for those in stage 1 and 2. You can worsen the problem if you use icy water for these pets. But for heat stroke, there is no time.


Veterinary intervention

You should always call your vet if you are concerned your pet is showing signs that indicate the heat is affecting them. Heat related illness can lead to multi-organ failure, including brain damage. The cost of treatment can go into the thousands, oxygen therapy, fluid therapy, potentially blood transfusion, seizure management, and a long hospital stay. Prognosis is very guarded to poor for heat stroke but beginning intervention prior to vet travel could save their life.