A man and his dog on the Overhanging Rock in Yosemite National Park, May 1924

HEAT CRAMPS

Symptoms:

Painful muscle cramps and spasms usually in legs and abdomen
Heavy sweating

First Aid:

Apply firm pressure on cramping muscles or gentle massage to relieve spasm.
Give sips of water, if nausea occurs, discontinue water

HEAT EXHAUSTION

Symptoms:

Heavy sweating
Weakness
Cool, pale, clammy skin
Weak pulse
Possible muscle cramps
Dizziness
Nausea and vomiting
Fainting
Normal temperature possible

First Aid:

Move person to a cooler environment
Remove or loosen clothing
Apply cool, wet cloths
Fan or move victim to air conditioned room
Offer sips of water. If nausea occurs, discontinue water. If vomiting continues, seek immediate medical attention.

HEAT STROKE (or sunstroke)

Symptoms:

Altered mental state
Possible throbbing headache, confusion, nausea, dizziness, shallow breathing
High body temperature (106°F or higher)
Skin may be hot and dry, or patient may be sweating
Rapid pulse
Possible unconsciousness

First Aid:

Heat stroke is a severe medical emergency. Summon emergency medical assistance or get the victim to a hospital immediately. Delay can be fatal.
Move the victim to a cooler, preferably air-conditioned, environment
Reduce body temperature with a water mister and fan or sponging
Use fan if heat index temperatures are below the high 90s
Use extreme caution
If temperature rises again, repeat process
Do NOT give fluids

The Hazards of Excessive Heat