Which of the following best defines heat stroke?

• A. A mild heat discomfort that resolves with rest
• B. Cold-related shivering and numbness
• C. Confusion, loss of consciousness, convulsions, lack of sweating and high body temperature
• D. A skin rash due to heat

Answer: (C)

Heat stroke is the most severe heat illness and happens when the body's cooling system fails during heat exposure. The defining signs are a very high body temperature (often above 40°C or 104°F) along with significant nervous system impairment, such as confusion, loss of consciousness, or seizures, and typically little or no sweating. This combination indicates the body cannot regulate its temperature and is a medical emergency requiring immediate cooling and professional medical care.

The other options describe different problems: mild heat discomfort that resolves with rest points to milder heat-related illness, cold-related shivering and numbness fits frostbite/frostnip, and a skin rash due to heat describes heat rash. None of these involve the extreme hyperthermia with CNS dysfunction that characterizes heat stroke.