Written by Lauren Murphy, SIU School of Medicine
Whether you’re visiting the local waterpark, playing sports outdoors, working in your garden or resting in a car on a warm summer day, hot temperatures could spell a heat-related illness like heat exhaustion or heat stroke. While heat stroke and heat exhaustion both exist on a spectrum, the illnesses manifest themselves quite differently, and one could be fatal. Do you know the differences?
HEAT EXHAUSTION
What is it?
The body is able to cool itself by sweating, but if sweating is unable to dissipate the heat generated within the body, heat exhaustion can occur. Often dehydration will also occur because the affected individual hasn’t replaced the water lost through sweating.
Symptoms include:
Profuse sweating
Weakness
Nausea
Vomiting
Headache
Lightheadedness
Muscle cramps
Treatment:
Move to a cooler environment
Rehydrate with water or a sports drink
If you are unable to keep water down due to vomiting, intravenous fluids may be necessary

HEAT STROKE
What is it?
Heat stroke is a form of hyperthermia, meaning the body temperature is dramatically elevated to 104 degrees F or higher. If not treated promptly or properly, it can lead to death.
Symptoms include:
High body temperature
No sweating with hot red or flushed, dry skin
Rapid pulse
Difficulty breathing
Strange behavior
Confusion
Hallucinations and disorientation
Agitation
Seizure and/or coma
How to treat it:
Always call 911 if heat stroke is suspected.
Get the affected person to a shaded area, remove his/her clothing, apply cool water to the skin and place ice packs under the armpits and groin.
If the person is able to drink, give them cool water or other cool beverages that do not contain caffeine or alcohol.
Monitor his/her body temperature with a thermometer and continue cooling efforts until the body temp drops to 101-102 degrees F.
Prevent heat-related illnesses
“It is critical to stay hydrated during the summer months,” advises Dr. Wendy El-Amin, a family medicine physician at SIU School of Medicine. “Consider hydrating yourself before becoming physically active outside in the heat and replenishing yourself with water every 20 minutes.”
It’s also important to be aware of which populations are most susceptible to heat related illnesses. “Our most vulnerable populations affected by heat stroke and heat exhaustion are children below the age of 4 and adults older than 65,” explains Dr. El-Amin.
The family medicine physician also reminds people to be aware of certain medications, such as those for high blood pressure, that place people at a higher risk for heat stroke and heat exhaustion.
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