By Dial A Vet Veterinary Team
In people, heat rash happens when sweat ducts block and trap sweat under the skin. Dogs sweat mainly through their paw pads, not their skin, so the classic human version is not really a canine diagnosis. When owners describe heat rash in a dog, they usually mean red, irritated skin that appears in hot, humid weather, most often on the belly, groin, armpits or in skin folds. That is real and worth treating. But in an Australian summer, the bigger worry is not the skin. It is heat stress, which can turn into life-threatening heatstroke within minutes.
Key takeaways
- What looks like heat rash in dogs is usually skin fold dermatitis, contact irritation, sunburn, bacterial infection or allergy flaring in the heat.
- Red skin in summer often needs a vet to identify the true cause.
- Heavy panting, drooling, wobbliness, vomiting or collapse in hot weather can mean heatstroke. Cool with tap water and go to a vet immediately.
- Flat-faced breeds, overweight dogs, senior dogs and thick-coated dogs are at highest risk of heat illness.
- Avoid human creams, essential oils and tea tree oil on summer skin problems.
What "heat rash" usually turns out to be
Skin fold dermatitis (intertrigo)
Warm, moist skin folds are perfect for bacteria and yeast to overgrow. Bulldogs, Pugs, Shar Peis and overweight dogs develop red, smelly, sometimes weepy skin in face, lip, neck, tail and body folds. Humid weather makes it worse.
Bacterial skin infection
Red bumps and pustules on the belly and groin often flare in summer, when heat, moisture, swimming and allergies combine.
Contact irritation
Lying on hot pavers, synthetic turf, freshly cut grass or treated surfaces can cause red belly skin. Wandering trad thrives in damp summer gardens.
Sunburn
White, pink-skinned and thinly coated dogs, such as white Staffordshire Bull Terriers, Bull Terriers, Dalmatians and Whippets, can burn on the nose, ear tips and belly. Repeated sunburn in Australia is linked to skin cancer.
Allergy flares
Grass pollens peak in spring and summer, so allergic dogs often itch more in the warmer months.
Burns
Hot bitumen, sand and metal surfaces can burn paw pads and belly skin in minutes. If the back of your hand cannot rest comfortably on the ground for seven seconds, it is too hot for paws.
Signs to look for
- Red, inflamed skin on the belly, groin, armpits or in skin folds
- Small bumps or pustules
- Itching, licking or rubbing
- Odour or moist discharge in skin folds
- Peeling, red skin on the nose or ear tips (sunburn)
- Blistered or raw paw pads (burns)
Heat stress triage
This is the part that saves lives. Dogs cool mainly by panting, which works poorly in hot, humid conditions. Watch for these signs whenever it is warm, even on days that do not feel extreme to you.
Early heat stress:
- Heavy, noisy panting that does not settle with rest in the shade
- Seeking shade or cool surfaces, reluctance to keep walking
- Thick drool
Heatstroke (emergency):
- Bright red, dark red or purple gums, or very pale gums
- Wobbliness, confusion or collapse
- Vomiting or diarrhoea, sometimes with blood
- Seizures
- Very fast breathing or noisy, struggling breaths
What to do immediately:
- Move your dog into shade or air conditioning.
- Wet your dog with cool tap water, not iced water, and use a fan or open car windows to help evaporation.
- Offer small amounts of water if your dog is alert.
- Call your vet and head in straight away, continuing to cool on the way. Heatstroke can damage organs even after a dog seems to recover.
Do not wrap your dog in wet towels, which trap heat. Never leave a dog in a parked car, even with windows down.
Who is at highest risk?
- Flat-faced (brachycephalic) breeds such as Pugs, French Bulldogs, Bulldogs and Cavalier King Charles Spaniels
- Overweight dogs
- Senior dogs and puppies
- Thick or double-coated breeds
- Dogs with heart or breathing problems, or laryngeal paralysis
- Working and very active dogs who keep going despite the heat
When to see a vet
Emergency: any sign of heatstroke.
Within a day or two: skin redness that is spreading, smelly, oozing or painful; burns to paws or skin; sunburn with blistering.
Routine: recurrent summer skin problems, so your vet can plan prevention before next season.
Keeping skin healthy in summer
- Walk early in the morning or in the evening, and avoid hot surfaces.
- Provide shade, cool tiles, a cooling mat and plenty of fresh water.
- Dry your dog thoroughly after swimming, including skin folds.
- Clean skin folds as your vet recommends.
- Ask your vet about pet-safe sunscreen for pink-skinned dogs, and keep them out of midday sun.
- Brush regularly to remove loose undercoat. Avoid shaving double-coated dogs right down.
- Keep up year-round flea control.
For more on belly irritation in summer, read our article on heat rash on a dog's belly.
FAQ
Can dogs really get heat rash?
Not in the same way people do, but heat and humidity can trigger or worsen several skin problems that look like it.
Is human sunscreen safe for dogs?
Some human sunscreens contain zinc oxide or other ingredients that are harmful if licked. Use a product made for pets.
What temperature is too hot to walk my dog?
There is no single number. Humidity, surface temperature, breed and fitness all matter. On hot days, walk early or late and test the ground with your hand.
Should I shave my dog in summer?
A tidy trim is fine, but shaving double-coated breeds to the skin can increase sunburn risk and does not necessarily keep them cooler.
Talk with a vet
A Dial A Vet veterinarian can look at photos of your dog's summer skin problem and help you decide whether it needs treatment. Book a Dial A Vet consult. If you suspect heatstroke, start cooling and go to your nearest vet or emergency hospital now.
References
- Hall EJ, Carter AJ, O'Neill DG. Incidence and risk factors for heat-related illness (heatstroke) in UK dogs under primary veterinary care in 2016. Scientific Reports. 2020;10:9128.
- Merck Veterinary Manual: Heatstroke in animals
- RSPCA Australia: Keeping pets safe in hot weather
- Merck Veterinary Manual: Skin fold dermatitis (intertrigo)
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.