A dangerously overheated body, usually in response to prolonged, hot, humid weather.


Hyperthermia occurs when the body's heat-regulating mechanisms don't work effectively. Older age, certain illnesses and medications increase the risk of developing hyperthermia.


A temperature of 104 F (40 C) or higher is life-threatening. Confusion, nausea or vomiting, and rapid breathing are some symptoms.


It's critical to move a person with hyperthermia to a cooler place and seek emergency care.

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