Preventing Heat Stroke in Dogs

“Sunny and 70” can mean “sunny and deadly”
By Shea Cox DVM, September 2011, Updated July 2020
signs of heat stroke dog

We have been experiencing idyllic temperatures in Berkeley, Calif., these past couple of weeks—mostly sunny days and mid-70s bliss. Perfect weather for a fun-filled outing with our pets, right? For the most part, the answer is “yes” but these are the kind of days where we have to be extra cautious with our pets as a dog can still easily overheat. At the veterinary hospital where I practice, I have had three dogs die from heat stoke in the past three weeks. These were not dogs left in unattended cars or as the result of negligent owners. They were really the result of not realizing that “sunny and 70” can mean “sunny and deadly.”

Two of the deaths were Bulldogs, one who played ball for a short 20 minutes outside and the other who went on his “normal daily walk.” The third loss was a Golden Retriever; the owner let him play at the park for an hour with the neighborhood kids, who always loved to spend time with him, such heartbreaking loss for everyone involved.

Many people are unaware of how dogs process heat and how easily dogs can succumb to heat stroke. Dogs cannot tolerate high temperatures as well as humans because they depend upon rapid breathing (panting) to exchange their warm body air for cooler environmental air. Therefore, when the air temperature is close to body temperature, cooling by rapid breathing is no longer an efficient process, and dogs can succumb to heat stroke in a relatively short time period.

Common Causes of Heat Stroke

Leaving a dog in the car with “the windows cracked.” We all still see this despite the warnings. Here’s the math: When left in a car on a relatively cool 75-degree day, the temperature within a vehicle can increase an average of 40°F within one hour. That equates to 115°F in the car, whether the windows are “cracked” or not.

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When an animal is left outdoors or exercised in hot or humid weather. I have treated many pets that have developed heat stroke while out for a routine walk, such as the Bulldog. One contributing factor is the fact that short-legged dogs are closer to the pavement, which radiates additional heat, contributing to the development of heat stress or stroke. It is important that dogs have adequate shade when outdoors.

Other factors that increase the risk of heat stroke include obesity and being a brachycephalic (short-nosed) breed such as a Pekingese, Pug, Lhasa Apso, Boston Terrier or Bulldog. These dogs suffer from ineffectual panter syndrome, which basically means that their elongated palate in a short face interferes with their ability to pant and can be fatal.

Signs Of Heat Stroke In Dogs

The normal body temperature of a dog is 101.5°F ±1. A temperature above 103°F is considered abnormal and heat exhaustion for dogs. Heat stroke, officially known as hyperthermia, occurs any time a dog’s body temperature is higher than 105°F. Heat Stroke is a truly life-threatening emergency that requires immediate recognition and prompt treatment.

At the onset of heat stroke, the dog appears distressed, will pant excessively and become restless. As the heat stroke progresses, the dog may drool large amounts of saliva from the nose and/or mouth. The dog may even become unsteady on his feet. You may notice the gums turning blue/purple or bright red, which is due to inadequate oxygen.

  • Distressed and restlessness behaviors
  • Excessive panting
  • Excessively drooling from nose or mouth
  • Blue/purple or bright red gums
  • Brightened tongue
  • Increased heart rate
  • Vomiting

Severe heat stroke is a disease that affects nearly every system in the dog’s body. Simply lowering the body temperature fails to address the potentially catastrophic events that often accompany this disorder. A dog suffering from heat stroke should be seen by a veterinarian as soon as possible for appropriate care. There are many life-threatening after affects that happen to a dog’s body following an episode of heat stroke, and early treatment will give your dog the best chance for survival.

How to Treat Heat Stroke in Dogs

  • Immediately, move your dog to shaded and cool environment.
  • Direct a fan on to the dog.
  • If possible, determine rectal temperature and record it.
  • Begin to cool the body by placing cool, wet towels over the dog’s back of the neck, in the armpits and in the groin region.
  • Wet the dog’s ear flaps and paws with cool water.
  • Direct the fan to the wet areas to speed up evaporative cooling.
  • Transport to the closest available veterinary facility immediately.

What NOT to do during a heat stroke:

Rapidly cooling off the dog is extremely important but do not use cold water or ice for cooling! While ice or cold water may seem logical, its use is not advised. Cooling of the innermost structures of the dog’s body will actually be delayed, as ice or cold water will cause superficial blood vessels to shrink (vasoconstrict), effectively forming an insulating layer of tissue to hold the heat inside. Tap water is more suitable for effective cooling.

Keep an eye on your pet and do not leave them unattended for any length of time. Do not attempt to force water into your dog’s mouth, but you may have fresh cool water ready to offer should your dog be alert and show an interest in drinking.

Most dogs with heat stroke have body temperatures greater than 105°F, and a reasonable goal of cooling is to reduce your pet’s body temperature to between 102.5°F and 103°F while transporting him or her to the closest veterinary facility.

What if I see a pet in distress?

California law now prohibits leaving dogs unattended in a vehicle, but I still see this (“grrrrrr”) all of the time. Since each state and local governments have different laws, if you do happen see a pet in distress, you can call the local animal control agency, police or 911 for assistance. Any peace officer, humane officer or animal control officer is authorized to take all steps necessary for the removal of an animal from a motor vehicle.

I have also made a downloadable flyer for you to print and leave on car windshields if you notice a dog inside of a vehicle. I wanted to create way to educate others instead of just getting worried, upset and frustrated. I know it is just a small gesture, but if it can save one dog’s life, then I’ve done my job with it.

Photo by fPat Murray

Shea Cox earned a veterinary medical degree from Michigan State University in 2001 and has been practicing emergency and critical care medicine since. In 2006, she joined PETS Referral Center. In her spare time, she loves to paint, wield her green thumb and cook up a storm. She shares her days with the three loves of her life: her husband Scott and their two Doberman.