What is heat stroke?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Heat stroke happens when your body’s normal temperature regulation fails in response to a very hot environment. Here’s how it happens: As sweat dries or evaporates off of your skin, it carries with it some of the heat your body makes. This allows you to stay around a perfect 98.6°F needed for your body to work properly. However, on hot, humid days, sweat doesn’t evaporate as easily from your body since there’s already a lot of moisture in the air. That means the body heat that sweat would normally carry away gets stuck on your skin, making it tough for you to cool down.

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Heat stroke is the least common but most severe heat-related illness. It usually occurs when people ignore the signs of heat exhaustion. Heat stroke develops when the body systems are overwhelmed by heat and begin to stop functioning. Heat stroke is a serious medical emergency.
Brett Snodgrass
Oncology Nursing

Heat stroke is the most severe of the heat related illnesses. It is the body’s inability to maintain temperature through sweating. It is so dangerous because heat stroke can quickly lead to seizures, organ failure and ultimately death. Early signs include nausea, vomiting, lethargy, increased heart rate, decrease or absence of sweating, red face, and fatigue.

Heat stroke is the most serious heat-related illness. It occurs when the body becomes unable to control its temperature. Body temperature rises rapidly, the sweating mechanism fails, and the body is unable to cool down. Body temperature may rise to 106°F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency cooling does not occur.
(This answer provided for NATA by the Marist College Athletic Training Education Program.)
Heat stroke occurs when the body can no longer sweat to cool itself while the body temperature is rising. This is a rare but serious condition and requires immediate medical attention.

A person with heat stroke generally shows signs of confusion or delirium or has lost consciousness. The skin can be hot, dry, red or flushed.

Due to the severity of the consequences of heat stroke, immediate medical attention must be given.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.