First Aid for Heatstroke

ByJanis Updated

Heatstroke is a severe and potentially fatal condition caused by the body overheating, usually due to prolonged exposure to high temperatures or strenuous activity in hot conditions. It occurs when the body’s internal temperature rises above 104°F (40°C) and it can no longer cool itself effectively. This can result in damage to the brain, heart, kidneys, and muscles if not treated promptly.

Common Causes of Heatstroke

Heatstroke may happen during:

  • Vigorous physical activity in hot or humid weather.
  • Sitting or working in an environment without adequate cooling or ventilation.
  • Wearing excessive or non-breathable clothing.
  • Prolonged exposure to the sun without hydration.
  • Certain medications or underlying health conditions that interfere with thermoregulation.

Infants, older adults, athletes, and people with chronic conditions are particularly at risk.

Signs and Symptoms of Heatstroke

Recognizing heatstroke early is crucial. Common symptoms include:

  • Extremely high body temperature (above 104°F or 40°C)
  • Hot, dry skin (or profuse sweating in exertional heatstroke)
  • Confusion or disorientation
  • Slurred speech
  • Rapid, strong pulse
  • Throbbing headache
  • Nausea and vomiting
  • Flushed or red skin
  • Seizures
  • Loss of consciousness

Not all symptoms may appear at once. Always take early warning signs seriously, especially if they follow heat exhaustion symptoms like heavy sweating and fatigue.

What You Can Do at Home or on the Scene

Step 1: Call for Help

Call 911 or emergency services immediately. Heatstroke is a medical emergency, and delays can be fatal.

Step 2: Begin Rapid Cooling

While waiting for help:

  • Move the person to a shaded or air-conditioned area.
  • Remove any excess or tight clothing.
  • Cool the person using the following methods:
    • Spray or sponge the body with cool (not cold) water.
    • Place ice packs under the armpits, groin, neck, and back.
    • Use a fan or any airflow to speed evaporation.
    • Immerse in a cool bath if possible and safe to do so.

Do not use ice water or cold showers in elderly individuals or children, as it can cause shock.

Step 3: Monitor and Support

  • If the person is conscious and alert, offer cool fluids (preferably water or an electrolyte drink). Do not force fluids.
  • Do not give salt tablets, caffeine, or alcohol.
  • If the person becomes unresponsive, check breathing and pulse.
  • If there is no breathing or pulse, begin CPR immediately if trained.
  • Place the person on their side if they are vomiting or unconscious but breathing.

When to Seek Emergency Help

Always seek professional medical attention if someone:

  • Has a core temperature over 104°F (40°C)
  • Faints, becomes confused, or is unresponsive
  • Has a seizure
  • Stops sweating in extreme heat
  • Vomits persistently or is unable to drink fluids

Even if symptoms seem to improve, medical evaluation is important to rule out organ damage and complications.

What to Avoid

  • Do not give fluids to someone who is unconscious or semi-conscious.
  • Do not use rubbing alcohol to cool the body.
  • Avoid cold water or ice if it causes shivering, which generates heat.
  • Don’t wait to see if symptoms go away—act fast.

Who Is Most at Risk

  • Infants and children (their bodies heat up faster).
  • Older adults (age 65+).
  • People with chronic illnesses like heart disease, diabetes, or respiratory conditions.
  • Individuals on medications that affect hydration or thermoregulation (diuretics, antihistamines, beta-blockers).
  • Athletes or laborers working in hot environments.
  • People without air conditioning during heatwaves.

Recovery and Follow-Up

Recovery depends on how quickly treatment is initiated and how severe the heatstroke was. After emergency care:

  • Individuals may need IV fluids, oxygen therapy, or hospitalization.
  • Rest and hydration are key.
  • Avoid heat exposure until cleared by a healthcare provider.
  • Watch for delayed complications, such as kidney or liver issues.

Prevention Tips

You can help prevent heatstroke by taking the following steps:

  • Stay hydrated—drink water consistently, not just when you’re thirsty.
  • Wear lightweight, loose-fitting, and light-colored clothing.
  • Avoid strenuous activity during the hottest parts of the day (typically 10 a.m. to 4 p.m.).
  • Take frequent breaks in shaded or cool areas.
  • Use fans or air conditioning indoors.
  • Monitor weather alerts and avoid outdoor activities during heat advisories.
  • Never leave anyone—especially children or pets—inside a parked car.

Health Writer

Janis's areas of expertise include nutrition, exercise, stress management, and mental health. She is passionate about educating and empowering people to take control of their health and make positive changes that can last a lifetime. Janis believes that small, sustainable changes are the key to long-term success, and she works with her clients to develop personalized plans that fit their individual needs and lifestyles.