📅 Last updated: June 2026 | ⏱ 6 min read | 🏷 Dog Care · Health & Safety
Dogs can’t sweat the way humans do — they regulate body temperature almost entirely through panting. That means when temperatures rise, dogs are at serious risk of overheating much faster than their owners realize. Knowing the early warning signs of heat stress can be the difference between a quick cool-down and a life-threatening emergency.
Here are 10 signs your dog is too hot, what each one means, and exactly what to do if you spot them.
Two things put this topic on my radar. First, summer real estate work means a lot of time outside — driveways, open houses, clients walking properties in July heat with their dogs in tow. I’ve watched dogs panting heavily outside a showing while their owners were inside, and more than once thought “that animal needs water and shade right now.” Second, spending summer time with family members’ dogs made me start paying attention more deliberately — once you’re building a site about dog care, you stop being a passive observer and start actually watching. The signs I’d always half-noticed suddenly had names.
1. Excessive Panting
Panting is normal — it’s your dog’s primary cooling mechanism. But excessive panting that’s louder, faster, or more labored than usual is a key early warning sign of overheating. If your dog is panting so hard their sides are heaving and they can’t seem to catch their breath, it’s time to act.
What to do: Move your dog to a cool, shaded area immediately. Offer fresh cool (not ice cold) water.
2. Excessive Drooling
Dogs drool more when they’re hot — this is part of the evaporative cooling process. But thick, ropy, or unusually heavy drool that doesn’t match your dog’s normal baseline is a warning sign that their body is working too hard to cool down.
What to do: Get your dog out of the heat and offer water. Wipe excess saliva from their mouth and chin.
3. Bright Red or Dark Gums
Healthy dog gums should be pink and moist. Gums that turn bright red indicate the body is rushing blood to the surface to cool down — a sign of heat stress. Gums that turn pale, white, or bluish are a sign of shock and require immediate emergency care.
What to do: Check gums regularly on hot days. Any color abnormality = immediate vet contact.
This is the check most owners never think to do. It takes three seconds and it’s one of the most reliable early indicators you have. Make it a habit on hot days — morning and afternoon. Pink and moist means you’re good. Anything else, act immediately.
“Most owners never think to check their dog’s gums. It takes three seconds and it’s one of the most reliable early heat-stress indicators you have. Make it a summer habit.”
4. Rapid or Irregular Heartbeat
Place your hand on your dog’s chest — a racing or irregular heartbeat in hot weather is a serious warning sign. A dog’s normal resting heart rate is 60–140 beats per minute depending on size. During heat stress, the heart works overtime to pump blood for cooling.
What to do: If the heartbeat feels unusually fast or erratic alongside other symptoms, call your vet immediately.
5. Lethargy or Weakness
A dog that suddenly becomes sluggish, uninterested in movement, or unusually quiet on a hot day may be experiencing heat exhaustion. This is especially concerning if your dog was active just minutes before.
What to do: Move your dog to a cool area immediately. Don’t encourage exercise. Offer water and monitor closely.
This is the sign I noticed most watching dogs at outdoor summer events — the shift from active to flat. A dog that was trotting around ten minutes ago and is now lying down with no interest in moving isn’t just tired. On a hot day, that change in energy is a flag worth taking seriously.
6. Vomiting or Diarrhea
Heat stress can trigger gastrointestinal distress. If your dog vomits or has diarrhea during or after time in the heat, their body is under significant strain. This can also lead to rapid dehydration, which compounds the problem quickly.
What to do: Stop all activity, move to cool area, offer small amounts of water, and contact your vet if symptoms persist.
7. Glazed or Unfocused Eyes
A dog that’s overheating may have a distant, glassy, or unfocused look in their eyes. This is a sign that blood flow to the brain may be compromised — a serious indicator that heatstroke may be developing.
What to do: This symptom requires immediate cooling measures and veterinary contact. Do not wait.
8. Stumbling or Loss of Coordination
If your dog stumbles, staggers, or has trouble walking straight in the heat, this is a neurological warning sign of advanced heat stress. The brain is highly sensitive to elevated body temperature — a core temperature above 104°F (40°C) can cause rapid neurological damage in dogs.
What to do: This is a veterinary emergency. Begin cooling immediately (cool — not cold — water on paws, armpits, groin) and rush to the vet.
9. Seeking Cool Surfaces or Refusing to Move
Dogs are instinctively smart about heat. A dog that’s pressing against cool tile floors, lying flat on shaded ground, or refusing to walk any further is telling you something important — their body temperature is too high and they need relief now.
What to do: Don’t push an overheated dog to keep walking. Let them rest on a cool surface and bring water to them.
I’ve seen this at summer showings more than once — a dog planted on the cool tile just inside the front door while the owners are outside in the heat. The dog knew. The owners hadn’t noticed yet. When a dog chooses a surface and won’t leave it, that’s not stubbornness. That’s self-preservation. Listen to it.
10. Collapse or Loss of Consciousness
Collapse is the most severe sign of heatstroke and represents a medical emergency. If a dog collapses and is unresponsive or seizing, every minute matters.
What to do: Begin cooling with cool (not ice cold) water on the neck, armpits, and groin. Do NOT submerge in ice water. Call your emergency vet immediately and keep them as cool as possible during transport.
“When a dog chooses a cool surface and refuses to leave it, that’s not stubbornness — that’s self-preservation. The dog is telling you something. Listen to it before you get to sign number 10.”
How to Cool Down an Overheated Dog
- Move to shade or air conditioning immediately — stop all activity.
- Offer cool fresh water — let them drink at their own pace. Don’t force it.
- Apply cool (not cold) water to paw pads, neck, armpits, and groin area.
- Use a fan to increase evaporative cooling while applying water.
- Do NOT use ice or ice water — it causes blood vessels to constrict and can trap heat inside the body.
- Place on a cooling mat — pressure-activated cooling mats can help regulate body temperature safely. See our guide to the best cooling dog beds and mats.
- Call your vet — even if your dog seems to recover, vet evaluation is recommended after any heat stress episode. Internal damage may not be immediately visible.
What We’d Actually Buy: For any dog that spends time outdoors in summer — or lives with someone who does — a pressure-activated cooling mat is the single most practical investment you can make. No electricity, no freezing required, and the dog self-regulates by lying on it when they need it. Our cooling dog bed guide covers the best options at every price point. Pair that with a collapsible water bowl for walks and you’ve covered the two biggest preventable gaps.
Which Dogs Are Most at Risk?
While any dog can overheat, certain dogs are significantly more vulnerable:
- Brachycephalic breeds (Bulldogs, Pugs, French Bulldogs, Boxers) — their shortened airways make panting less effective
- Senior dogs — less efficient at regulating body temperature
- Overweight dogs — extra body mass generates more heat
- Puppies — immature thermoregulation systems
- Dogs with thick double coats (Huskies, Malamutes, Samoyeds)
- Dogs with heart or respiratory conditions
Summer Safety Tips to Prevent Overheating
- Walk dogs in the early morning or evening — never during peak afternoon heat
- Always carry water on walks — collapsible bowls are easy to pack
- Never leave a dog in a parked car — temperatures rise dangerously within minutes
- Provide constant access to shade and fresh water outdoors
- Use a cooling mat indoors — especially for breeds prone to overheating
- Consider a well-fitted harness instead of a collar on hot days — collars can restrict airflow around the neck
- Know your dog’s normal baseline — the better you know what’s normal, the faster you’ll catch warning signs
Frequently Asked Questions
What temperature is too hot for dogs?
Most dogs are comfortable up to around 85°F (29°C) in moderate humidity. Above 90°F (32°C) — especially with high humidity — all dogs face elevated risk of heat stress, particularly during exercise. Brachycephalic breeds and senior dogs are at risk at even lower temperatures.
How long does it take for a dog to overheat?
Faster than most owners expect. A dog left in a parked car on a 70°F day can experience dangerous temperatures within 10 minutes. During exercise in hot weather, heat stress can develop in 15–30 minutes for susceptible breeds.
Can I use ice to cool my dog down?
No. Ice and ice-cold water cause blood vessels near the skin to constrict, which can trap heat inside the body and make the situation worse. Use cool (not cold) water and focus on the paw pads, armpits, neck, and groin for fastest cooling.
Should I take my dog to the vet after overheating?
Yes — even if your dog appears to recover fully. Heat stress can cause internal organ damage (kidneys, liver, brain) that isn’t immediately visible. A vet check after any significant overheating episode is always the right call.