Heatstroke: First aid


Heatstroke happens when body temperature rises quickly and a person can't cool down. It can be life-threatening by causing damage to the brain and other vital organs. It may be caused by doing strenuous activity in the heat or by being in a hot place for too long. Heatstroke can happen without having any previous heat-related condition, such as heat exhaustion.

When to seek emergency help

If you suspect heatstroke, call 911 or your local emergency number. Then move the person out of the heat right away.


Heatstroke symptoms include:

  • Fever of 104 degrees Fahrenheit (40 degrees Celsius) or greater.
  • Changes in mental status or behavior, such as confusion, agitation and slurred speech.
  • Hot, dry skin or heavy sweating.
  • Nausea and vomiting.
  • Flushed skin.
  • Rapid pulse.
  • Rapid breathing.
  • Headache.
  • Fainting.
  • Seizure.
  • Coma.


For heatstroke, cool the person through whatever means available. For example:

  1. Put the person in a cool tub of water or a cool shower.
  2. Spray the person with a garden hose.
  3. Sponge the person with cool water.
  4. Fan the person while misting with cool water.
  5. Place ice packs or cool, wet towels on the neck, armpits and groin.
  6. Cover the person with cool, damp sheets.
  7. If the person is conscious, offer chilled water, a sports drink containing electrolytes or another nonalcoholic beverage without caffeine.
  8. Begin CPR if the person loses consciousness and shows no signs of circulation, such as breathing, coughing or movement.

Last Updated May 29, 2024

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