Hyperthermia & Heat Stroke In Dogs: Symptoms, Causes, & Treatments

Dog left in the car

(Picture Credit: Getty Images)

Hyperthermia and heat stroke in dogs are conditions characterized by elevated body temperatures beyond the normal range. Hyperthermia, which is generally defined as a body temperature in dogs above 103 degrees Fahrenheit, can either be fever or non-fever. Fever hyperthermia happens when the body experiences inflammation, which can be caused by a number of factors, including bacterial infection. Non-fever hyperthermia happens when dogs cannot regulate their body temperature through panting to keep up with external heat. Heat stroke is a form of non-fever hyperthermia where body temperatures climb above 106 degrees Fahrenheit with no signs of inflammation. Hyperthermia and heat stroke can result in loss of consciousness, organ failure, and death if they go untreated. If you see the signs of hyperthermia or heat stroke in your dog, it is important that you take steps to cool your dog and consult your veterinarian right away. Here is what you should know about the symptoms, cause, and treatments for hyperthermia in dogs.

Symptoms Of Hyperthermia & Heat Stroke In Dogs

Focus face old dog sleep on wood floor in hot weather

(Picture Credit: Getty Images)

They symptoms of hyperthermia and heat stroke in dogs can vary in severity based on how long a dog suffers from these conditions without treatment and how elevated their body temperature is. Although fever and non-fever hyperthermias, including heat stroke, have different causes, the symptoms are similar. If you see the following symptoms of hyperthermia or heat stroke in your dog, take steps to cool them down and get to a vet for treatment.

  • Panting and drooling
  • Thick saliva
  • Dehydration
  • Body temperature above 103 degrees Fahrenheit (106 degrees for heat stroke)
  • Red gums and tongue
  • Decreased urination
  • Weakness
  • Mood changes
  • Unsteady gait
  • Dizziness
  • Tachycardia (rapid heart beat)
  • Arrhythmia (irregular heart beat)
  • Fluid in the lungs, which causes breathing problems
  • Diarrhea
  • Black, tarry stools
  • Vomiting blood
  • Blood clotting disorders
  • Small pinpoints of blood appearing on the body
  • Inflammation all over the body
  • Shock
  • Cardiopulmonary arrest (heart and breathing stops)
  • Kidney failure
  • Liver damage
  • Seizures
  • Tremors
  • Loss of consciousness
  • Coma

Causes Of Hyperthermia & Heat Stroke In Dogs

Dogs waiting in cars, looking through windows

(Picture Credit: Getty Images)

There are several possible causes of hyperthermia and heat stroke in dogs. The most obvious cause of heat stroke is being exposed to heat and humidity for an extended period of time. Usually this happens when dogs are confined to enclosed spaces that are poorly ventilated, such as a car, a small room, or a dryer cage at a groomer. This can also happen when dogs excessively exercise in heat without taking a break and cooling off. Heat stroke is exacerbated by dehydration, so not having access to water can worsen the condition.

Some dogs are more at risk for developing heat stroke. Dogs with long coats, dogs that aren’t used to a hot environment and are suddenly exposed, obese dogs, and brachycephalic dogs (dogs with short snouts) are more susceptible to heat stroke. Conditions like heart, nervous system, or blood diseases also put dogs more at risk.

Malignant hyperthermia happens when dogs have a reaction to substances like anesthesia or caffeine, or when they have a chemical reaction to stress. These reactions raise the body temperature. Some dogs are predisposed to this disorder, especially Labrador Retrievers. Exposure to poisons like snail bait may cause seizures, which can lead to elevated body temperatures.

Non-fever hyperthermia can also happen when thyroid hormones are elevated or when there is damage to the hypothalamus, which is the area of dogs’ brains that regulates body temperature. Fever hyperthermia is usually caused by inflammation that results from a bacterial or other infection in the body.

Treatments For Hyperthermia & Heat Stroke In Dogs

Wet dog with towel on head

(Picture Credit: Getty Images)

Treatment for hyperthermia and heat stroke in dogs should begin at the earliest signs of symptoms. If you see the signs of hyperthermia or heat stroke in your dog, try to make sure they are removed from any dangerous environment, such as a hot car, and placed somewhere where they can begin to cool off. You may wish to spray or immerse your dog in cool water, not cold water, if it is available. Wrapping them in cool, wet towels, cooling them with fans, or placing isopropyl alcohol on the footpads, groin, or armpits can help.

Do not use cold water. This can cause blood vessels to constrict and decrease your dog’s ability to release heat. Also, if they start shivering, it can create internal heat, which will worsen the condition. Lowering body temperature too quickly can lead to other health problems.

Seek veterinary attention as soon as your dog is removed from any dangerous environment. They may need to be treated with intravenous fluids, oxygen therapy, and sedation until their temperature stabilizes and falls below 103 degrees Fahrenheit. Some dogs may need to have their windpipe surgically opened if they have trouble breathing. Your dog will need to be checked for signs of organ damage and treated accordingly. If there is an underlying infection that is causing the hyperthermia symptoms, it will be treated with medication.

Dogs that have experienced hyperthermia are at greater risk for experiencing it again. If your dog has suffered from hyperthermia, your veterinarian will make recommendations for avoiding future occurrences and let you know which factors contribute to the condition. Follow your veterinarian’s instructions closely.

Around The Web

Breed Profile Finder