By Mayo Clinic Staff

Overview

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.

Symptoms

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.

Treatment

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.

From Mayo Clinic to your inbox

Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

May 29, 2024