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Maintaining body temperature

When things go wrong - heat stroke

Heat stroke is an uncontrolled increase in body temperature.


Heat stroke is caused by:

  • high temperatures which cause an increase in sweating. This can lead to dehydration which reduces sweating which then allows the core body temperature to rise.
  • not drinking sufficient water when hot

As the core body temperature rises, the normal mechanisms for controlling body temperature break down. This can lead to a further rise in the core body temperature.


The symptoms of heat stroke are:

  • increased body temperature
  • hot, dry skin
  • rapid heartbeat
  • increased or decreased blood pressure
  • headache
  • confusion
  • unconsciousness.


  • Move the person to a cool, shady place.
  • Cool the person by covering them with damp sheets or spraying them with water.
  • Cool the person with a fan.
  • Seek professional medical help.

Back to Homeostasis index

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