Heat exhaustion is one of the heat-related syndromes. These syndromes range in severity and seriousness from mild to potentially life-threatening. Other types of heat-related illnesses include heat rash, heat cramps, heat syncope and heatstroke.
Heat exhaustion can occur when your body loses too much water or salt — usually as a result of excessive sweating or dehydration. It can begin suddenly or happen over time, usually after working, exercising or playing in the heat.
Heat exhaustion signs and symptoms include:
- Cool, moist skin with goose bumps when in the heat
- Heavy sweating
- Faintness
- Dizziness
- Fatigue
- Weak, rapid pulse
- Low blood pressure upon standing
- 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 elevate the legs and feet slightly.
- Remove tight or heavy clothing.
- Have the person sip chilled water, a decaffeinated sports drink containing electrolytes or other nonalcoholic beverage without caffeine.
- Cool the person by spraying or sponging with cool water and fanning.
- Monitor the person carefully.
Contact a health care provider if signs or symptoms worsen 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 he or she experiences:
- Fainting
- Agitation
- Confusion
- Seizures
- Inability to drink
- Core body temperature — measured by rectal thermometer — of 104 F (40 C) (heatstroke)
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April 15, 2022
- Ishimine P. Heat illness (other than heat stroke) in children. //www.uptodate.com/contents/search. Accessed Feb. 24, 2022.
- Heat stress. Centers for Disease Control and Prevention. //www.cdc.gov/niosh/topics/heatstress/. Accessed Feb. 24, 2022.
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- Heatstroke and heat exhaustion
Heatwaves and hot weather can kill. Learn about the signs, symptoms and treatment of heatstroke and heat exhaustion so you can help yourself and others when the temperature soars.
Heatwaves can kill, so learn how to stay cool in hot weather and watch for the signs and symptoms of heat exhaustion and heat stroke. Here's what to look for and what you can do to help. Note that risk of heat related illness can increase with young children and elderly, pregnancy and those taking certain medications. Here's what to look for and what you can do to help.
What is heat exhaustion?
Heat exhaustion happens when someone becomes dehydrated due to fluid loss from a hot environment and/or excessive physical activity
Heat exhaustion signs and symptoms
- Headache
- Body temperature more than 40 degrees Celsius
- Muscle cramps
- Exhaustion and general weakness.
- Nausea and/or vomiting
- Dizzy spells
- Pale, cool, clammy skin at first, becoming flushed and red later
- A rapid, weak pulse.
Heat exhaustion treatment
- Help the person to lie down at total rest in a cool or shady area to monitor
- Remove excessive clothing and loosen any tight clothing
- Cool by fanning and moisten skin if possible
- If fully alert and responsive, give them frequent small drinks of water
- If muscle cramps occur, gently stretch the affected muscles to ease pain
- If unresponsive, place in the recovery position.
- If the person is unable to drink vomiting, unresponsive ,or does not improve call 000 for an ambulance
- Prepare to give CPR if necessary.
What is heat stroke?
Heat stroke is a life-threatening emergency and can cause a person to collapse or fall unconscious Heat stroke is more serious and means the body is no longer able to regulate its temperature by cooling the skin's surface by sweating. The internal body temperature rises, and organ damage can occur.
Heat stroke signs and symptoms
- Typically no longer sweating.
- Red, hot and dry skin.
- A body temperature more than 40°C.
- A rapid, strong pulse.
- Rapid, noisy breathing.
- Irrational or aggressive behaviour.
- Deterioration of the conscious state.
Heat stroke treatment
- Call 000 for an ambulance immediately
- Cool the person using wet towels or a wet sheet with a fan directed across the surface.
- If ice packs are available, wrap them in towels and place them around the neck groin and armpits .
- If shivering occurs reduce active cooling.
- Monitor the person continually
- If unresponsive or not alert , place in the recovery position.
- Prepare to give CPR if necessary.
For more information, download the Red Cross First Aid App.