Heat exhaustion is one of the heat-related syndromes. These syndromes vary in seriousness, ranging from mild to possibly life-threatening. Other types of heat-related illnesses include heat rash, heat cramps, heat syncope and heatstroke.
Heat exhaustion can happen when the body loses too much water or salt — usually because of heavy sweating or dehydration. It can begin suddenly or happen over time, usually after working, exercising or playing in the heat.
Heat exhaustion symptoms include:
- Cool, moist skin with goose bumps when in the heat.
- Heavy sweating.
- Faintness.
- Dizziness.
- Fatigue.
- Weak, rapid pulse.
- Low blood pressure after standing up.
- Muscle cramps.
- Nausea or vomiting.
- Headache.
- Extreme thirst.
- Mild confusion.
- Decreased urine output.
If you suspect heat exhaustion
Untreated, heat exhaustion can lead to heatstroke, which is a life-threatening condition. If you suspect heat exhaustion, take these steps immediately:
- Move the person out of the heat and into a shady or air-conditioned place.
- Lay the person down and raise the legs and feet slightly.
- Remove tight or heavy clothing.
- Have the person sip chilled water, a sports drink containing electrolytes or another nonalcoholic beverage without caffeine.
- Cool the person by spraying or sponging with cool water and fanning.
- Monitor the person carefully.
Contact a healthcare professional if symptoms get worse or if the person doesn't improve after taking first-aid measures.
Call 911 or your local emergency number if the person's condition gets worse, especially if the person:
- Faints.
- Becomes agitated.
- Is confused.
- Has a seizure.
- Is not able to drink.
- Has a core body temperature — measured with a rectal thermometer — of 104 degrees Fahrenheit (40 degrees Celsius), which indicates heatstroke.
March 06, 2024
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