A quick look under your dog’s lip can reveal an important warning. Healthy gums should be pink, while bright red, dark red, blue, grey or unusually pale gums can signal that something is wrong, particularly when the change appears with persistent panting or unusual behavior.
Gum color alone cannot confirm heatstroke. The RSPCA notes that red gums may have other causes, including dental problems, but says redness combined with panting and heavy breathing can occur when a dog is overheating.
Michael Sheils, a brand ambassador for UK dog-grooming supplier Christie’s Direct, advises owners to watch for rapid, extremely loud or frantic panting that continues while a dog rests in shade. Restlessness, pacing, anxious wandering and attempts to hide are also concerning changes.
Other warning signs identified in RSPCA heatstroke guidance include noisy breathing, confusion, weakness, unusual tiredness, thick drool, vomiting, diarrhea, muscle spasms, collapse or seizures. A dog does not need to display every sign before an owner acts.
Exercise is a leading heatstroke trigger
The RSPCA identifies exercise as the most common trigger for canine heatstroke. It recommends adjusting a dog’s routine to the weather rather than relying on one temperature as a safe cutoff for every animal.
That distinction matters because heat vulnerability varies. Puppies and senior dogs may have more difficulty regulating their temperature, while overweight dogs and those with airway, lung or heart conditions face added risk. Thick coats can retain heat, and flat-faced dogs may be unable to pant as effectively because of their shorter muzzles.
All dogs can develop heatstroke, however. Heat-related illness can follow strenuous activity or exposure to a hot or humid environment, and dogs rely primarily on panting to release heat. Owners should watch the individual dog’s breathing, movement and behavior instead of assuming that a familiar walk is safe under changed conditions.
Cornell veterinary guidance recommends moving walks to the early morning or evening, avoiding strenuous exercise during the hottest parts of the day and providing shade and frequent opportunities to drink. On days of extreme heat or humidity, keeping a dog cool indoors may be the safer choice.
Cool first, then seek veterinary care
Heatstroke is a medical emergency because prolonged overheating can damage organs. If a dog has concerning signs, stop exercise, move the animal away from direct sun or another heat source and begin cooling immediately.
The Royal Veterinary College recommends a “cool first, transport second” response. Move the dog to a cool, well-ventilated place, offer small sips of water without forcing the dog to drink, and pour water that is cooler than the dog over the body while creating airflow with a fan, breeze or air conditioning.
Cold-water immersion can be effective for a young, otherwise healthy dog, according to the college. For older dogs or those with underlying health problems, it recommends pouring or spraying cooler water over the body while using moving air. An unconscious dog should not be immersed.
The RSPCA advises avoiding the head when pouring water because a dog with heatstroke may already be struggling to breathe. Its guidance directs owners to concentrate water on the neck, stomach and thighs and to keep air moving around the wet dog.
Call a veterinarian as soon as cooling has started and explain that heatstroke is suspected. Continue to a veterinary hospital in a cooled, well-ventilated vehicle as directed. Veterinary assessment remains important even if the dog appears to improve because serious consequences may not be immediately apparent.
Difficulty breathing, continued excessive panting or drooling, vomiting, weakness, confusion, seizures or collapse require immediate veterinary care. Owners should not wait for gum color to change or for several symptoms to appear before seeking help.
Preparedness means knowing your dog’s individual risk factors, changing activity when conditions change and understanding the first steps before an emergency develops. Recognizing persistent panting, abnormal gums and behavioral changes early can shorten the time a dog remains overheated while veterinary help is arranged. What would you do if your dog were in this situation? Share your thoughts in the comments.
By Sarah Mitchell — 8 years as a local-news reporter covering animal welfare, shelters, neighborhood disputes, and public-safety pet stories.
