Spot heatstroke in a dog by watching for heavy panting, excessive drooling, weakness, confusion or collapse. Move the dog to a cool place, begin cooling with cool—not ice-cold—water, and seek emergency veterinary care immediately.
Heatstroke can worsen quickly, and cooling at home is not a substitute for veterinary treatment. A dog may be in danger after exertion or time in a hot environment; do not wait for symptoms to become severe before acting.
This guide explains how to recognise heatstroke in dogs, what to do while arranging urgent care, and which common responses can make the situation worse.
| Sign or situation | Immediate action | Why it matters |
|---|---|---|
| Heavy panting or breathing difficulty | Stop activity; move to shade and cool the body | May indicate difficulty losing heat |
| Weakness, stupor or collapse | Begin cooling and seek emergency veterinary care | Altered responsiveness is a serious warning sign |
| Vomiting, bloody diarrhoea or seizures | Arrange emergency veterinary care immediately | These signs can accompany severe heat illness |
| Hot car or heated building | Remove the dog and start cooling | Enclosed heat can rise rapidly |
- nearly 70% Dogs with exercise-induced heatstroke that became unwell after just going for a walk on a hot day
- above 80% Humidity level that can negate evaporative heat loss
- 120 ?F in less than 20 minutes Possible temperature inside a sun-exposed closed car when the outdoor temperature is 75 ?F
- 105.8°F (41°C) Core-temperature threshold in the clinical description of heatstroke with central nervous system dysfunction
What should you do first if your dog may have heatstroke?
If your dog may have heatstroke, stop exercise, move them into shade or a cooler place, start cooling them with water, and call a veterinary clinic while arranging emergency care.
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Leave the heat. Move your dog out of direct sun, a hot vehicle or a heated building. Take them to shade or another cooler place and stop them from moving around.
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Wet the body. Use cool water from a hose or bucket, keeping it away from your dog’s face. Don’t wait to see whether a move to shade alone helps.
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Use a fan. Direct airflow over your dog’s damp skin to support evaporative cooling. Keep cooling them as you prepare to leave for veterinary care.
Call the clinic and go
Call a veterinary clinic and say that you suspect heatstroke. Arrange emergency veterinary care and begin transport promptly; cooling at home is not a reason to wait and see whether your dog improves enough to avoid a visit.
What signs mean heatstroke is an emergency?
Persistent, excessive panting, difficulty breathing, marked weakness, reduced responsiveness, vomiting, bloody diarrhoea, seizures or collapse make suspected heatstroke an emergency requiring urgent veterinary attention.
Heatstroke can disrupt a dog’s ability to lose heat: panting that remains intense, or breathing that becomes difficult, is a warning sign. Weakness or depression may progress to stupor or collapse, so changes in alertness and response matter as much as breathing.
- Breathing: Persistent excessive panting or difficulty breathing.
- Behaviour and responsiveness: Weakness, depression, stupor or collapse.
- Severe signs: Vomiting, bloody vomit, bloody diarrhoea, seizures or coma.
A temperature above 105.8°F (41°C) together with dysfunction of the central nervous system is a clinical description of heatstroke in dogs. Do not wait for every sign to appear: bloody vomit or diarrhoea, a seizure, coma or collapse warrants urgent veterinary care.
Why can a short walk become dangerous?
A short walk can become dangerous because exercise produces body heat, and hot weather makes it harder for a dog to lose that heat while moving. The Kennel Club says nearly 70% of dogs with exercise-induced heatstroke became unwell after just going for a walk on a hot day.
In hot conditions, continued movement adds to the dog’s heat load instead of giving the body time to recover. Even gentle exercise can be enough to trigger heatstroke, so a familiar route is not automatically safe when the weather is hot.
Which dogs need closer supervision?
- Flat-faced dogs can be especially susceptible to heat, so watch their activity closely.
- Overweight dogs and seniors also need closer supervision during exercise in hot weather.
- Working dogs need access to shade, water and rest. Iowa Veterinary Specialties warns that they can develop hyperthermia when these are unavailable.
For any dog, stop activity and provide a chance to rest in shade rather than encouraging it to keep moving through the heat.
Why can humidity make cooling harder?
Humidity makes cooling harder because dogs depend on panting and evaporation to release body heat, and damp air limits how well moisture evaporates. Iowa Veterinary Specialties says humidity above 80% can negate evaporative heat loss.
A fan directed over wet skin can help moisture evaporate, but humid air may reduce that benefit. Airflow is not a substitute for veterinary care when heatstroke is suspected.
Cool the dog and the surroundings
Move your dog to a cooler environment as well as wetting them with water. When the air feels humid, changing the surroundings matters: wetting the coat alone may not allow enough evaporation to cool the dog effectively. You can use a hose or bucket to wet the dog, avoiding the face, and direct a fan over the damp skin while arranging veterinary care.
If your dog may have heatstroke, do not wait to see whether a fan is enough. Cooling measures support the response, but they do not replace prompt veterinary attention.
Why is a parked car an emergency risk?
A parked car is an emergency risk because sunlight can heat its closed interior to dangerous levels even when the air outside feels moderate. Iowa Veterinary Specialties says a closed car exposed to sun may exceed 120 ?F in less than 20 minutes when the outside temperature is only 75 ?F.
Shade outside the car does not make it safe for a dog to remain inside: the enclosed space can still be hot. Take the dog out of the vehicle and into a cooler place immediately.
What to do
Begin cooling the dog while arranging emergency veterinary care. Wet the dog with water, avoiding the face, and use a fan over damp skin if available. Do not delay transport while trying to cool the dog fully; contact an emergency veterinarian and follow their instructions.
Which cooling mistakes can make the situation worse?
Cooling a dog with an ice bath, wrapping them in a wet towel or pouring water over their face can make heatstroke response less safe; use controlled cooling while arranging veterinary care.
- Ice bath: Avoid it. Cooling too rapidly can be harmful; wet the dog’s body with cool water instead, keeping the face clear.
- Wet towel: Do not wrap one around the dog. It can trap heat against the body rather than help it escape.
- Water on the face: Keep water away from the face to protect the airway. Apply it to the body.
Cool ceramic tile or a cooling mat can make a dog more comfortable, and drinking water or a frozen dog treat can support comfort. These are not treatments for suspected heatstroke and should not delay emergency veterinary assessment.
If you suspect heatstroke, keep cooling the dog’s body in a controlled way as you arrange veterinary care. Offer drinking water, but do not let a cooling mat, tile or treat take the place of urgent assessment.
Frequently asked questions
Should I wait to see if my dog improves after cooling?
Can a walk on a hot day cause heatstroke?
Is a wet towel a safe way to cool a dog?
Can humidity affect cooling?
Key takeaways
- Stop activity, move the dog to shade and begin wetting the body promptly.
- Excessive panting, breathing difficulty, weakness, vomiting, collapse or seizures warrant emergency veterinary care.
- A short hot-weather walk can trigger exercise-induced heatstroke, according to the Kennel Club.
- Avoid ice baths and wet-towel wraps; use water on the body and airflow over damp skin.
Sources
- animalemergencyservice.com.au — “Heat Stroke In Dogs – Signs, Symptoms & Treatment”
- rspca.org.uk — “How to Recognise & Treat Heatstroke in Dogs – RSPCA – rspca.org.uk”
- American Red Cross — “Pet Heat Safety – Can Pets Get Heat Stroke?”
- PetMD — “Heatstroke in Dogs: Signs, Treatment, and Prevention”
- Today's Veterinary Practice — “Heatstroke in Dogs”