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Heatstroke is when your body severely overheats. Heatstroke happens when you do physical activity in hot conditions without drinking enough liquids. Normally, the body has a cooling system that is controlled by the brain. The cooling system adjusts to hot conditions and lowers your body temperature by producing sweat. With heatstroke, the body's cooling system is not working well and results in an increased body temperature.


Call your local emergency number (911 in the US) if:

  • You cannot stop vomiting.
  • You are confused or cannot think clearly.
  • You cannot move your arms and legs.

Return to the emergency department if:

  • Your temperature is 104°F (40°C) or higher.
  • You feel faint, dizzy, weak, or tired.
  • You breathe fast or feel like your heart is beating faster than normal.

Call your doctor if:

  • Your skin is red and dry.
  • You have muscle cramps or twitching.
  • You have nausea and vomiting.
  • You have numbness or prickling feeling in your arms or legs.
  • You have questions or concerns about your condition or care.

First aid for heatstroke:

  • Move to an air-conditioned location or a cool, shady area and lie down. Raise your legs above the level of your heart.
  • Drink cold liquid, such as water or a sports drink.
  • Mist yourself with cold water or pour cool water on your head, neck, and clothes.
  • Apply ice packs on your neck, armpits, and groin.
  • Loosen or remove as many clothes as possible.
  • Have someone call 911 immediately for medical assistance.

Prevent heatstroke:

  • Wear lightweight, loose, and light-colored clothing.
  • Protect your head and neck with a hat or umbrella when you are outdoors.
  • Drink lots of water or sports drinks. Avoid alcohol.
  • Eat salty foods, such as salted crackers and salted pretzels.
  • Limit your activities during the hottest time of the day. This is usually late morning through early afternoon.
  • Use air conditioners or fans and have enough proper ventilation. If there is no air conditioning available, keep your windows open so air can circulate.
  • Never leave children alone inside cars, especially during hot weather.

Follow up with your doctor as directed:

Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Learn more about Heatstroke (Aftercare Instructions)

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IBM Watson Micromedex

Further information

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