The three types of heat illnesses are heat cramps (often caused by dehydration), heat exhaustion (also caused by dehydration), and heat stroke (shock, a medical emergency). Remove the victim from the heat, take off their clothing, and have them lie down. Apply ice or cool compresses, elevate the feet, give the victim fluids if they are able to drink, and use a fan to blow cool air. Get immediate medical help for heat stroke.
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