With the longer days and warmer weather, we naturally start spending more time outdoors, and so do our pets. It means that we’re more active, but heat and increased levels of activity in our pets can increase the risks of heat exhaustion, or hyperthermia.


Hyperthermia is a rise in body temperature above the normal range. Heat stroke is a form of non-fever hyperthermia that occurs when the body cannot accommodate excessive external heat, leading to organ dysfunction and eventually failure.


It occurs more commonly in dogs than in cats. It can affect any breed, but it is more frequent in long-haired dogs as well as short-nosed, flat-faced dogs such as Pugs, and Persian cats, as they are less efficient at eliminating heat. Elderly, overweight and sick animals are also more likely to suffer.


The thick fur coats of dogs and cats can make it more difficult for them to control their temperatures in the heat of summer and they can become distressed quite quickly if left outdoors in the heat. It’s important to be wary of the signs that your pet could be suffering and know what to do if they are. One of the most obvious signs is that they will pant more heavily as this is the way they try to manage their temperature, rather than sweating like we do.  Other signs that your pet could be suffering include:


  • Drooling
  • Laboured breathing and an increased heart rate
  • Reddened gums
  • Production of only small amounts of urine or no urine
  • Vomiting
  • Diarrhoea
  • Black, tarry stools
  • Wobbly, uncoordinated gait or movement

The effects can be devastating. They include:


  • Seizures
  • Kidney failure
  • Shock
  • Unconsciousness/coma
  • Death


You may notice your pet attempting to manage their temperature by laying on a cool tiled floor or in the shade. It’s important to be aware of these signs that they’re feeling the heat and to avoid activities that will contribute to their discomfort. Outdoor time will be better in the early morning or in the evening. It will be easier for them to breathe and the ground will be cooler on their paws. This is particularly important when walking dogs and as a rule of thumb, if the ground is too hot for you to walk on in bare feet then it’s too hot for your dog as well.


Things that can cause hyperthermia include:


•Excessive exercise

•Excessive environmental heat and humidity

•Diseases that affect breathing

•Poisoning – compounds in slug and snail bait, for example, can lead to muscle twitching which can cause an abnormal increase in body temperature


Early recognition of the signs of heat stroke are vitally important in an animal’s recovery and if you suspect that your pet is suffering heatstroke the first step is to lower their body temperature. If increased body temperature appears to be a result of environmental temperature caused for example by exercise, the weather, or an enclosed room or cage, then lower their body temperature by draping a cold wet towel over them or immersing them in a cool bath.


Maintain airflow over their body with a fan or air conditioner, and get them drinking water. Avoid ice or very cold water, as this may cause blood vessels near the surface of the body to constrict and may decrease heat dissipation. A shivering response also is undesirable, as it creates internal heat. Lowering the temperature too quickly can lead to other health problems, a gradual lowering is best. The same approach applies to drinking water, allow your pet to drink cool, but not cold water, and do not force them to drink.

As with all illnesses, prevention is better than cure. Animals who have suffered an episode of hyperthermia are prone to experiencing it again. Be aware of the signs of heat stroke so you can respond quickly. Talk to your vet about safe ways to lower your pet’s temperature and exercise common sense. Sometimes it’s better to leave pets at home when going out on hot days regardless of how much they may want to join you. If they come with you they’ll need shade, just as we would, and leaving them at home under cover might be the most sensible approach. Importantly, never leave your pet in a parked car, even for only a few minutes, as a closed car becomes dangerously hot very rapidly.


Be aware of the following risk factors of hyperthermia. They could make your pet more susceptible:


•Previous history of heat-related disease

•Age extremes (very young, very old)

•Heat intolerance due to poor acclimatisation to the environment (such as a heavy coated dog in a hot geographical location)


•Thick hair coat

•Short-nosed, flat-faced breeds

•Dehydration, insufficient water intake, restricted access to water




Seek veterinary assistance as soon as possible if your pet is suffering heat stroke. Examination by a veterinarian will be necessary to ensure that a normal temperature has been reached, and that no long lasting damage has occurred. In many cases patients need to be hospitalised until their temperature has stabilised and may even need intensive care.


Vigilance and common sense go a long way in ensuring that your pet remains safe in the heat of summer. Keep a close eye on them and be aware of the warning signs that they may be distressed and situations that can lead to trouble. Their desire to be with you may override their choices of cooler and safer options, therefore it’s important to make sensible decisions for them. Being aware of the risks and knowing how to avoid them can help you to ensure they have a safe and happy summer.