Heatstroke is a dangerous medical emergency that happens when your body gets so overheated that it can't cool itself down anymore. Normal body temperature is around 98.6°F, but during heatstroke, it can spike to 104°F or higher. At these temperatures, the brain, heart, and other organs can start to malfunction, which is why heatstroke can be life-threatening without quick treatment.

Your body usually cools itself through sweating, but heatstroke occurs when this system fails, often during intense physical activity in hot weather or from being stuck in extreme heat for too long. A football player practicing in full gear on a scorching afternoon might develop heatstroke. So might someone trapped in a hot car or working outside in a heat wave without enough water or rest.

Warning signs include confusion, dizziness, a rapid heartbeat, hot and dry skin (though sometimes the person is still sweating), and severe headache. Someone with heatstroke needs immediate medical help and rapid cooling with ice packs or cold water while waiting for help.

Heatstroke is more severe than heat exhaustion, which makes you feel sick and weak but doesn't cause the same dangerous rise in body temperature. Prevention matters: drinking plenty of water, taking breaks in the shade, and knowing when conditions are too extreme for outdoor activities. Athletes, outdoor workers, and elderly people face higher risk during heat waves.