Heatstroke in Dogs

Summer in Australia can be unforgiving, and our dogs feel the heat long before we do.

Dogs can’t cool themselves efficiently. They rely almost entirely on panting, minimal sweating through their paw pads, and small amounts of heat loss through their ears and nose.

When temperature, humidity, exertion, or confinement overwhelm these mechanisms, heatstroke can develop rapidly.

Heatstroke progresses fast and can become life-threatening within minutes.

Lets look at the early signs most owners miss, natural support, prevention strategies, high-risk dogs, and when emergency veterinary care is essential.

Panting is one of the main ways dogs cool themselves

What Is Heatstroke in Dogs?

Heatstroke (hyperthermia) occurs when a dog’s internal temperature rises faster than the body can cool itself. Once the temperature reaches dangerous levels:

• metabolic processes fail

• inflammation and clotting disorders develop

• gut lining becomes “leaky”

• cells are damaged

• organs begin to fail

• neurological signs can occur

Heatstroke is always an emergency in dogs.

They cannot safely “cool down” on their own once they begin to overheat.

How Dogs Cool Themselves

Dogs cool themselves very differently from humans.

Dogs can’t sweat across their skin, so their entire cooling system relies on a few key mechanisms.

The most important is panting: as they breathe rapidly, moisture evaporates from the tongue, mouth, and upper airway, pulling heat away from the body. Dogs also lose small amounts of heat through their paw pads and by lying on cool surfaces, which draw warmth out through conduction. Airflow across the coat also helps, when a breeze or fan moves over the fur, it carries heat away from the surface of the body.

These systems work well in mild conditions, but they become overwhelmed quickly in hot, humid, or windless weather, which is why even short periods of heat can put dogs at risk.

A More Detailed Look at How Panting Cools Dogs

Panting is the dog’s primary cooling system, and it’s far more complex than simply “breathing fast.”

When a dog pants, the airflow over the tongue and through the upper airway causes moisture to evaporate. This evaporation is what pulls heat out of the blood circulating through the tongue, mouth, and respiratory tract.

As blood cools in these areas, it circulates back into the body and helps reduce internal temperature.

To make panting more efficient, dogs increase saliva production. This is why hot dogs drool more. Saliva spreads across the tongue and mouth, creating a moist surface area that evaporates quickly and removes heat more effectively.

Thick, sticky saliva, or saliva that dries fast is a sign that the dog is struggling to keep up with the heat.

Panting becomes less effective when:

• Humidity is high Moisture in the air slows evaporation, so each pant removes less heat.

• Airflow is low Still air means hot air is inhaled back into the body instead of being replaced with cooler air.

• The dog is anxious or overexcited Stress panting generates heat rather than removing it.

• The mouth dries out When saliva becomes tacky, evaporation slows dramatically.

• The dog has airway disease BOAS, laryngeal paralysis, or tracheal collapse make airflow inefficient.

Once panting and drooling can no longer evaporate enough moisture to remove heat from the bloodstream, internal temperature starts to rise and heatstroke begins to develop.

Humidity increases risk

Heatstroke is not just about temperature.

Humidity dramatically reduces panting efficiency because moisture cannot evaporate.

A 28°C humid day can be more dangerous than a 33°C dry day.

Signs your dog is struggling in humidity:

• panting that is loud or unproductive

• drooling

• a “wide” tongue

• refusing to walk

• restless behaviour

Humidity is especially dangerous for:

• brachycephalics

• senior dogs

• overweight dogs

• dogs with airway disease

Early Signs of Heatstroke (Often Missed)

These subtle signs are critical to recognise early:

• Slightly faster or heavier panting

• Seeking shade or cool surfaces

• Restlessness or pacing

• Drooling more than usual

• Warm gums, ears, or abdomen

• Sticky or tacky saliva

• Drinking more than usual

• Quietness or lethargy

• Reduced interest in walking

At this point, intervention can prevent escalation.

Moderate Signs (Heatstroke is Developing)

Cooling mechanisms are failing:

• Bright red, dark, or pale gums

• Very fast, noisy, or laboured breathing

• Thick, sticky drool

• Weakness or wobbling

• Rapid heart rate

• Vomiting or diarrhoea

• Dazed or confused behaviour

• Body hot to the touch

• Inability to settle

Begin cooling and arrange veterinary assessment immediately.

Severe Signs (Medical Emergency)

Indicates advanced heatstroke and possible organ damage:

• Collapse

• Tremors or seizures

• Severe vomiting or bloody diarrhoea

• Staggering, disorientation

• Blue, grey, or very pale gums

• Unresponsiveness

• Loss of consciousness

This is a medical emergency. Contact a vet and travel immediately.

Brachycephalic (short nosed) breeds are more at risk of heatstroke

Dogs Most at Risk of Heatstroke

Some dogs overheat far more easily:

Brachycephalic breeds

Cavoodles, Frenchies, Bulldogs, Pugs, Shih Tzus, Boxers.

Dogs with airway diseases

• Laryngeal paralysis

• Collapsing trachea

• Elongated soft palate

• Stenotic nares

• These dogs can overheat even on mild days.

Senior dogs

Reduced circulation + poor temperature regulation.

Overweight dogs

Extra fat insulates and traps heat.

Puppies

Immature cooling mechanisms + high activity.

Dark-coated dogs

Absorb solar heat quickly.

Double-coated / thick-coated dogs

Highly active or excitable dogs

Fetch, running, high arousal = rapid heat production.

Heat Triggers Most Often Overlooked

Dogs often overheat in these common scenarios:

Beach days

• hot sand

• reflective UV

• saltwater ingestion → dehydration

• excitement + sprinting

Car travel

Even a “quick stop” is deadly, temperatures in parked cars climb in minutes.

Walks on warm evenings

Ground retains heat long after sunset.

Wet coats or harnesses in the heat

They trap heat once they stop evaporating.

Clothing, booties, bandanas

Unless scientifically designed for cooling, they insulate.

A thick, padded harness can trap in heat and make it more difficult for dogs to cool themselves.

Safe Transport During Heat Events

If taking your dog to the vet:

• Pre-cool the car for 3–5 minutes

• Position your dog near airflow

• Keep windows partially open (only if safe)

• Continue gentle cooling with damp cloths

• Avoid restraining the head or neck

• For brachycephalics: keep the neck extended and airway open

Temperature Safety Guide for Dogs

Use this as a quick rule of thumb:

Temperature	Risk Level	Notes
<20°C	Safe for most dogs	Monitor brachycephalics on humid days
20–26°C	Caution	Heat-sensitive dogs may struggle
26–28°C	High risk	Avoid exercise for brachycephalics, seniors
28–30°C	Very high risk	Short outdoor time only
>30°C	Extreme danger	Heatstroke risk for all dogs

Natural Prevention Strategies

Exercise only early morning & late evening

Avoid 9am–7pm on warm days.

Provide multiple cooling opportunities

• shade

• fans

• cooling mats

• shallow shell pools

• damp towels for lying on (not over the body)

Support hydration

• Water in multiple locations

• Hydration slurries

• Goat milk or kefir splashes

• Cucumber and melon

• Electrolytes on extreme days (dog-safe only)

Keep coats brushed

Improves airflow and heat dissipation.

Avoid hot surfaces

If you can’t hold your hand on the pavement for 5 seconds, it’s too hot.

Never leave dogs in cars

Even “quick” errands can be fatal.

First Aid for Heat stroke in Dogs: How to Cool Your Dog Safely and Effectively

If your dog shows any signs of heat stress or heatstroke, begin cooling immediately while preparing to travel to the vet.

1. Move your dog to shade or air-conditioning

Good airflow is essential from the start.

2. Offer small amounts of cool (not icy) water

Allow gentle sipping only, gulping can trigger vomiting or aspiration.

3. Wet your dog thoroughly with cool water

Use a hose, shower, or bucket of cool (not cold) water.Focus on high-heat areas:

• paws

• legs

• belly

• groin

• chest

Why not ice-cold water?

Icy water causes the surface blood vessels to constrict, trapping heat inside the core and slowing cooling. It can also cause stress and shock. Cool or room-temperature water + airflow is the safest method.

4. Increase evaporation with airflow

Use a fan, car air-conditioning, or a natural breeze to help the water evaporate. This is the most effective way to remove heat.

5. Remove anything that traps heat

Take off:

• wet coats

• wet harnesses

• booties

• clothing

  These act as insulation once warm and can worsen overheating.

6. Keep your dog calm

Stress and panting increase heat production, so speak softly and minimise stimulation.

7. Do NOT use

• ice baths

• ice-cold hosing

• freezing water

• wrapping the dog in wet towels (they trap heat without airflow)

8. Seek veterinary care immediately

If your dog shows any moderate or severe signs, or does not improve within minutes, travel to your vet while continuing gentle cooling and airflow.

Post-Heatstroke Monitoring

Even if your dog appears recovered, complications can develop for 24–72 hours.

Watch for:

• Vomiting or diarrhoea

• Dark urine

• Excessive thirst or urination

• Lethargy

• Difficulty walking

• Mental dullness

• Reduced appetite

• Muscle tremors

Seek veterinary care if any of these appear.

Summer Heat Safety Checklist

• ☐ Walk before 9am or after 7pm

• ☐ Provide cool water everywhere your dog rests

• ☐ Offer hydration foods or electrolytes

• ☐ Use airflow: fans, shaded areas, ventilation

• ☐ Keep dog’s coat brushed

• ☐ Avoid hot cars and warm pavements

• ☐ Watch for early panting changes

• ☐ Know your dog’s risk category

Heatstroke is almost always preventable, yet the early signs are subtle and easy to miss.

By understanding how dogs regulate heat and acting quickly when something feels “off”, you can protect your dog from a potentially life-threatening emergency.

With simple daily adjustments, safe cooling strategies, and awareness of early warning signs, your dog can enjoy a comfortable, healthy summer, no matter how hot it gets.

If your dog is heat-sensitive, has chronic health issues, I’m here to help.

You can book an individualised Naturopathic Summer support plan here

Give your dog a pat from me.

Kerrie