What is Heat Stroke in Dogs and How is It Treated?

Heat stroke, which vets call hyperthermia, occurs when environmental factors cause a dog's body temperature to rise faster than they can cool down. A dog's average body temperature is usually around 101 to 102 degrees Fahrenheit. Anything above 103 degrees is typically considered elevated, and when it reaches 106 to 107 degrees, the dog is in great danger.

The most common cause of heat stroke in dogs is leaving the dog in a hot car. The glass windows in cars create a greenhouse effect, which causes rapid heat build-up. Dogs who are trapped in hot vehicles cannot pant enough to cool themselves down.

Dogs who are left outside without sufficient shade and water are also at a high risk of heat stroke. It can also happen when a dog is too active on hot days, such as if the dog tags along on a long hike when the temperatures are too hot.

The earliest symptoms of heat stroke are often mild and hard to notice. Your dog may seem a little tired lethargic. Mild confusion is common, which may be most obvious when you give your dog a command, and the dog doesn't respond. You may also notice your dog panting very fast and heavily.

If the heat stroke progresses, your dog may begin stumbling, drooling, or vomiting. Dogs experiencing heat stroke also typically have reddened gums and may become more confused and disoriented. Eventually, your dog may collapse or have seizures.

If you notice even minor signs of heat stroke, it's important to cool your dog's body down as soon as possible. If possible, put them in a bathtub full of cool water or run cold water from a hose over their back. If your dog won't let you do that or those options aren't available, soak a towel in cold water and drape that over your dog's back. Be sure to refresh it with cold water frequently.

While you do this, offer your dog cool, fresh water to drink. Let the dog drink as much as they are willing to, but don't force it — some dogs with severe heat stroke or unable to drink on their own.

If your dog starts showing more severe symptoms of heat stroke, you should call your vet while you administer first aid. Dogs who are stumbling, disoriented, or unable to stand need immediate veterinary care.

If you caught heat stroke early and your dog seems to be recovering, you may not need to rush right over to the vet's office, but you should still give them a call. Sometimes even mild heat stroke can cause internal damage or other lingering problems, so your veterinarian may want to examine your dog.

Once your dog is at the vet's office, the vet will generally continue to use cool water and other techniques to lower the dog's body temperature. The dog will also receive intravenous fluids to replace lost water and minerals. The veterinarian may also perform blood tests and other diagnostics to make sure the heat stroke hasn't caused organ damage or other internal problems.

Heat stroke should always be treated as a veterinary emergency. Even fairly mild cases can result in damage to the kidneys, brain, and other internal organs. Heat stroke that isn't treated promptly often results in permanent damage or death. If you suspect your dog may be developing heat stroke, don't take a wait and see approach. Begin first aid and call your veterinarian for assistance.

The best way to avoid heat stroke is to keep an eye on the temperature and take some extra precautions when it is hot. Leave your dog at home on warm, sunny days rather than going for a car ride while you run errands. Keep long walks, or strenuous exercise limited to early mornings and late evenings on hot days, or try exercises like swimming that help your dog stay cool. Make sure your dog always has a shady, well-ventilated place to relax outside, and remember that if it's too hot for you to be outdoors, it's too hot for your dog. Always provide plenty of cool, fresh water to your dog.

Some dogs are more prone to heat stroke than others. Dogs with thick, heavy double coats, such as huskies, tend to overheat faster than dogs with lighter coats. Older dogs are also more prone to it than younger dogs, and overweight dogs may struggle more as well. Brachycephalic dogs, which have very short muzzles, are also more prone to it since they can't pant as effectively. This includes breeds such as pugs, bulldogs, and boxers. Dogs who have had heat stroke before are more likely to get it again.

Most people only start worrying about heat stroke when the temperatures start soaring, but it can be a danger even at mild temperatures. When it comes to keeping dogs in cars, even 60-degree sunny days can be dangerous. The temperature inside a vehicle can rise to over 100 degrees in a matter of minutes because of the greenhouse effect. For outdoor activities, it depends on the dog's health, the humidity, and other factors, but it's a good idea to keep an eye out for signs of heat stroke on any warm day, especially during strenuous exercise.