Heat Exhaustion

Heat exhaustion is caused by insufficient water and salt intake, and a deficiency in the production of sweat. Heat exhaustion can occur anywhere there is poor air circulation, such as around an open furnace or heavy machinery, or outside in extremely warm temperatures if you are not used to being in the heat and humidity.

Those most prone to heat exhaustion are the elderly, people with high blood pressure and those who work or exercise in hot, humid environments. Heat exhaustion generally occurs several hours after exertion and dehydration. 

While not a life-threatening illness, heat exhaustion can lead to the more serious condition known as heat stroke if left untreated. Your temperature should be closely monitored to make sure it does not rise above 103 degrees. If it does, you will need to be treated immediately for heat stroke, which is a life-threatening illness.

Signs and Symptoms: 

  • Dry mouth
  • Nausea and/or vomiting
  • Headache
  • Rapid and weak pulse
  • Normal skin temperature, but damp and clammy feeling
  • Muscle cramps
  • Dizziness and disorientation


  • Move to cool place, either indoors or in the shade
  • Loosen clothing
  • Slowly drink cool water

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