The Walk Can Wait

Most heat-related illness in UK dogs begins with exercise. Sometimes cancelling the walk is the safest decision you can make.

We have become very good at warning people about hot cars. The message is familiar, memorable and necessary. Leave a dog inside a parked car on a warm day and the temperature can become dangerous with frightening speed.

But cars are not where most cases begin.

A large UK study looked at more than 1,200 incidents of heat-related illness recorded by veterinary practices. Almost three quarters followed exercise. By comparison, 12.9% were linked to environmental heat without exercise and 5.2% to being confined in a vehicle.

In many cases, the dog had simply been doing something they would do on any other day.

Why walking changes things

A dog produces heat as they move. Usually, panting allows enough of it to escape. Problems begin when the body is creating heat faster than it can lose it.

That can happen during a long walk, although distance is not the only concern. A few intense minutes chasing a ball may be harder on the body than a much slower wander. Hills, direct sun and humid air can also turn a familiar route into something more demanding.

The dog may still look delighted to be there. Excitement has a way of carrying some dogs past the point when they might otherwise rest, particularly when a ball or another dog is involved. Waiting for them to decide that they have had enough is not always a reliable plan.

Reading the weather and the dog

Temperature bands give us a useful place to begin. For dogs used to the UK climate, a day in the low twenties can already feel hot, especially when the sun is strong or the walk involves more than a gentle pace.

The same temperature can create very different conditions. A shaded woodland path with moving air is not the same as an open field at midday. Humidity can make panting less effective, while tarmac and paving may become much hotter than the surrounding air.

Then there is the dog themselves. Their age, health and physical build all change the calculation. So does the type of exercise being planned. The forecast may say one thing, while the dog and the route suggest another.

Dogs living in consistently warmer countries may also be more accustomed to heat than those experiencing a sudden spell of warm UK weather. This article, and the research behind it, focuses on dogs living in the UK.

Some dogs struggle sooner

Flat-faced dogs need particular care in warm weather. Their shortened skulls affect the space available within the upper airway, and many already work harder to breathe before heat or exercise is added.

When researchers studied dogs attending UK emergency clinics during the exceptionally hot summer of 2022, brachycephalic dogs were found to have more than four times the odds of heat-related illness compared with dogs of a moderate skull shape.

It cannot tell us exactly what will happen to an individual French Bulldog, Pug or Bulldog on a particular day. It does tell us that these dogs are reaching emergency care with heat-related illness far more often than their longer-nosed counterparts.

Older dogs may have a harder time too, as can dogs carrying excess weight or living with conditions that affect the heart or breathing. Heavy coats can hold warmth close to the body, while very large dogs produce more heat when they move. Any dog who has overheated before deserves extra caution in future.

The first signs are easy to dismiss

Panting is expected on a warm walk. What matters is whether it seems out of proportion to what the dog has been doing or continues to become heavier after they stop.

Some dogs begin looking for shade or lag behind. They may refuse to continue, drool more than usual or develop very red gums and tongue. Their breathing can become noisy or distressed. Vomiting and diarrhoea can appear as the illness develops.

At first, it may look as though the dog simply needs a drink and a short rest. This is the point to stop, find somewhere cool and begin taking the situation seriously.

Weakness, wobbling, confusion and collapse suggest that the illness has progressed. Seizures, bleeding or loss of consciousness are signs of severe heat-related illness, although veterinary help should have been sought long before they appear.

The difference between early and severe illness is considerable. One study found that 97.8% of dogs with mild heat-related illness survived, as did 94.5% of those with moderate illness. Survival among dogs with severe disease fell to 43.2%.

Cool first, then travel

If a dog appears to be overheating, move them out of the heat and begin cooling while someone contacts a vet. The phrase used by the Royal Veterinary College is “cool first, transport second”. It means that cooling should start immediately, rather than waiting until the dog reaches the practice.

Pour tap water that is cooler than the dog over their body, avoiding the nose and mouth. A fan, breeze or air conditioning will help heat leave the wet skin. A young, otherwise healthy dog may also be placed in cold water if this can be done safely and their head remains above the surface.

Wet towels should not be wrapped around an overheating dog. They warm quickly and can hold heat against the body. Ice and ice-cold water are also best avoided.

Cooling can continue on the journey where practical. Switch on the air conditioning or open the windows before putting the dog in the vehicle, and tell the veterinary team that you are coming.

A dog who appears brighter after cooling should still be discussed with a vet. Overheating can affect the kidneys, liver and clotting system, and the full extent of the damage may not be obvious from the outside.

It is fine to miss the walk

This is often the part owners find difficult. The dog has heard the lead move. They are waiting by the door, and staying at home feels like letting them down.

One missed walk will not harm them. Nor will several shorter outings during a spell of hot weather. Exercise can happen early in the morning or later in the evening, once the ground and the air have cooled. On some days, pottering in the garden or finding something quiet to do indoors will be enough.

Ball throwing deserves particular caution. The repetition creates heat quickly, while the excitement encourages many dogs to keep going. Even a slow walk can become uncomfortable when the route is exposed and there is nowhere cool to stop.

Warm-weather safety does not require a perfect calculation. It requires a willingness to change the plan when the day feels wrong for the dog in front of you.

The walk will still be there when it is cooler.