Heatstroke & Heat Exhaustion

How to avoid heat-related illnesses


Both heatstroke and heat exhaustion are illnesses caused by prolonged exposure to excessive high temperatures.

In Quebec, the recent heat wave in the month of June has claimed the lives of 54 individuals, this summer alone.

As temperatures soar, it is therefore important to know how to prevent, recognize and be able to rapidly treat symptoms of heat related illness.

Heat Exhaustion vs Heat Stroke

Heat exhaustion isn’t as serious as heat stroke, but can progress to a heat stroke, causing damage to the brain and other vital organs (lungs, liver, kidneys, muscle tissue), and even death, if it isn’t properly managed. Heat exhaustion and heat stroke can occur to anyone after they’ve been exposed to high temperatures. It is often accompanied by dehydration.

Signs and Symptoms

Heat Exhaustion

  • Excessive thirst
  • Excessive sweating
  • Headache
  • Nausea and vomiting
  • Muscle cramps
  • Dizziness
  • Loss of consciousness
  • General sense of weakness
  • Rapid, weak pulse
  • Dark coloured urine

Heat Stroke

  • ‍Hot dry skin
  • ‍Fever
  • ‍Racing heartbeat
  • ‍Confusion
  • ‍Agitation
  • ‍Slurred speech
  • ‍Seizures
  • ‍Loss of consciousness
  • ‍Coma

Causes & Risk Factors

Heat exhaustion and heat stroke can be exertional and non-exertional.

Exertional heat stroke happens when your body can no longer adapt to the rise in temperatures during exercise or work. It can happen over a few hours and typically affects people spending time outdoors.

Non-exertional heat stroke happens when your body is unable to adapt to increasingly hot temperatures, in the absence of any physical activity - for example, when staying indoors without proper air conditioning. It can happen over several days, and it common during extreme heat waves. Older adults, people suffering from chronic illnesses and young children are often more at risk.

Leaving young children or pets inside vehicles also puts them at risk of heat strokes.


Since heat exhaustion and heat stroke risk increase as the temperature rises, the best prevention is to keep your body cool.

Give the following tips a try:

  • Stay indoors during the hottest part of the day
  • Stay in the shade outdoors
  • Spend time in properly air conditioned rooms. Malls, coffee shops and libraries are good public options too!
  • Drink plenty of fluids, have an extra 2-4 cups of water every hour
  • Avoid drinks that can dehydrate, such as coffee or alcohol
  • Wear loose, light coloured clothing in breathable fabrics such as linen or cotton
  • Wear a hat to shield the face
  • Take frequent breaks during exercise


Caring for someone who exhibits symptoms of heat exhaustion or heat stroke is pretty straightforward:

Cool down the body temperature:

  • Stay out of the sun, remove articles of clothing, turn on the fan or air conditioning
  • Spray a cool mist, apply cold wet towels or ice packs to the body


  • Drink plenty of fluids. Make sure you are replenishing both water and electrolytes.

Rehydration salts like Gastrolyte are very handy to have at home and when travelling to a warm destination. It can be mixed in a glass of water and helps replenish essential electrolytes, glucose and salt. It can also help manage fluid loss due to vomiting or diarrhea.

Symptoms should improve promptly (within an hour). If that is not the case, it is best to consult a doctor. As well, if the person lost consciousness, is confused, or is extremely agitated, you can follow the steps above but also contact emergency medical services in the meantime.

Remember to listen to you body, most of the time heat strokes and heat exhaustion can be prevented.

Should you have any questions, don’t hesitate to send us a message at info@airix.ca.

Stay cool and safe!