Peoria, Ill.,
15:34 PM

Heat Exhaustion vs. Heat Stroke: Know the Difference

Man suffering from heat exhaustion

Illinois averages 10 days with temperatures at or above 90 degrees each year, according to the Illinois State Climatologist. 

In typical August fashion, temperatures have been reaching and topping the 90-degree mark this week.

This summer weather puts many people at risk for heat exhaustion and heat stroke. Not only outdoor workers, but kids, older adults and those without working A/C in their buildings could be affected.

Brian Curtis, MD, vice president of Clinical Specialty Services for OSF HealthCare, says preparation and awareness are keys to staying safe in the summer heat.

“You’ll go from heat exhaustion before you get to heat stroke,” Dr. Curtis says. “Heat exhaustion is where people are cool, clammy, sweating profusely, and they may have some nausea or vomiting. They usually have some severe muscle cramping with it.”

If heat exhaustion is not recognized and treated quickly, Dr. Curtis says heat stroke can then happen.

“With heat stroke, they’ll have dry skin, a temperature of 102-103 degrees, they’ll be confused or passed out,” Dr. Curtis says. “That’s a medical emergency, a 911 call. Whereas with heat exhaustion, you need to get them out of the heat, get them into a cool environment, and get them some liquids.”

Dr. Curtis says hospitals see heat stroke patients every summer, especially during longer stretches of hot and humid weather. He says higher humidity causes our bodies to not be able to cool as easily.

But these dangers don’t just affect outside workers or athletes playing sports in the summer. Dr. Curtis says the main excessive heat victims are middle-aged people, but kids and older adults are more susceptible.

“Because they don’t heat and cool themselves as easily, they’re more prone to get it, and we tend to be more vigilant with them,” Dr. Curtis says.

Heat exhaustion or heat stroke aren’t solely seen outside, either.

“If you get into the mid or upper 90s, we have some people around here who still don’t have air conditioning. You can get heat exhaustion and heat stroke within a building,” Dr. Curtis says. “When people don’t have air conditioning, that’s when you really see a lot of the elderly develop heat exhaustion within their own homes.”

Prevention of heat exhaustion and heat stroke

- Drink plenty of liquids (water, fruit juice, sports drinks)

- Avoid dehydrating liquids like alcohol and caffeinated beverages

- Take frequent breaks

- Get out of the sun and into the shade

- Use sunscreen and avoid getting sunburnt

- Use the buddy system: Keep an eye on each other

Dr. Curtis adds the effects of heat stroke can be long-lasting, or even lead to death.

“People die of it every year, or they have debilitating conditions afterwards,” Dr. Curtis says. “Once you’ve had heat stroke, you tend to be more susceptible to the heat as you go forward. Your body does not regulate as well and so you can be more prone to develop it in the future.”

For More Information

When it comes to extreme temperatures, play it safe. Know the warning signs of heat stroke and take the proper steps to prevent it.

Symptoms of Heat Exhaustion

  • Profuse sweating
  • Water depletion (causes extreme thirst)
  • Weakness
  • Dizziness
  • Salt depletion (causes muscle cramps)
  • Nausea
  • Vomiting
  • Fainting
  • Headache

Symptoms of Heat Stroke

  • Body temperature greater than 104° F (main sign)
  • No sweating in hot weather
  • Neurological problems such as confusion, unconsciousness, and seizures
  • Rapid breathing
  • Increased heart rate

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