Heat stroke is a dangerous and potentially deadly condition that can occur when the body reaches a temperature of 104 degrees Fahrenheit or higher. There are two types of heat stroke: exertional, which affects people who overexert themselves in hot environments; and passive, which typically affects older people (especially those who are also sedentary) who are exposed to high temperatures.
Either type of heat stroke can lead to brain damage, organ failure and even death, knowing the warning signs is important. Look for:
- High body temperature. A body temperature of 104 F (40 C) or higher is the main indicator of heatstroke.
- A sudden change in mental status. Seizures, loss of consciousness, confusion, hallucinations or difficulty speaking or understanding what others are saying are signs and symptoms that should alert you to heat stroke.
- A lack of sweating. In passive heatstroke, skin will feel hot and dry with no sweat. (Note that in exertional heatstroke, skin usually feels hot and moist.)
- Red, flushed skin.
- Rapid, shallow breathing.
- Racing heart rate. Pulse may significantly increase as the heart works harder to keep the body cool.
- Headache.
- Muscle cramps or muscle weakness. In the early stages of heatstroke, muscles may feel tender or cramped, and later become rigid or limp.
If you observe or experience any of these symptoms on a hot day – contact emergency services at once, seek shade immediately and take steps to cool off – remove clothing, pour or spray cool water on the skin, fan the body to help with evaporation, move the arms away from the body to give more surface area to cool and place ice wrapped in plastic or towels in the armpits

