Heat Stroke Treatment and Prevention


“It’s OK, I’m just a little lightheaded…?”

No way.

That’s just one typical symptom of heatstroke, a potentially fatal condition that’s an immediate 911 moment.

To frame the urgency: an epic 2003 heat wave in France left 15,000–18,000 dead.

Even when survived, heat stroke can leave the victim with brain or other organ damage—liver, kidneys, lungs, and heart.

Heat stroke is caused by over-exposure to high temperatures, usually accompanied by dehydration. When your temperature hits more than 105 degrees, your internal regulators crash and your overheated internal organs begin doing the same.

It can begin as a milder heat-related illness—heat cramps or heat exhaustion. But it also can strike with full force—without warning.

It’s important to know the typical symptoms of heat stroke. If you’re out in the heat, be wary if you or someone you’re with experiences:

  • Dizziness, light-headedness, fainting
  • Throbbing headache
  • Red, hot, dry skin with no sweating
  • Muscle weakness or cramps
  • Nausea and vomiting
  • Rapid heartbeat, either strong or weak
  • Rapid, shallow breathing
  • Confusion, disorientation, or staggering
  • Seizures, unconsciousness, or coma

Who gets heat stroke?

  1. Classic heatstroke develops over 2–3 days of exposure, typically among older (over 50), sedentary people with no air-conditioning who often have inadequate fluid intake.
  2. Exertional heatstroke occurs more suddenly and affects healthy, active people like athletes, military recruits, and factory workers. It’s the second leading cause of death in young athletes.

The causes and symptoms of heat stroke are similar in both groups.

The highest-risk group is older people with no air conditioning and limited airflow. Others include people of any age who don’t drink enough water, have a chronic disease, work or play too long in high heat, or drink excessive amounts of alcohol.

Other risk factors include:

Age: Children under 4 and adults over 65 adjust to heat less efficiently

Health conditions: Diabetes; heart, lung, or kidney disease; obesity or underweight; high blood pressure; alcoholism; sunburn and conditions that cause fever all signal increased risk.

Medications: Many medications increase the risk of heat stroke. Ask your doctor if yours are among them.

Now that you recognize the symptoms, what should you do about them?

Treating heat stroke

If you suspect someone has had a heat stroke, delay can kill. Call 911 immediately or get that person straight to a hospital.

If help is on the way, here are some immediate interventions you can perform, depending on location:

  • Move the person to a cooler space—air-conditioned, if possible, or anywhere cooler or shadier
  • Remove unnecessary clothing
  • If possible, take the person’s temperature

If the temperature is greater than 105 degrees, the goal is to cool it to 101–102 degrees. But if a thermometer isn’t handy, initiate first aid anyway. If it’s not heat stroke, no harm done. If it’s heat stroke, it could be a lifesaver.

You should also, if possible:

  • Fan the person while wetting his or her skin with water
  • Apply ice packs to the victim’s armpits, groin, neck, and back, where blood vessels are close to the skin
  • Immerse the patient in a shower or tub of cool water or an ice bath

Preventing heat stroke

When it’s very hot, heat wave or not, it’s best to stay in an air-cooled or air-conditioned environment—ideally, your own home.

If your home has no fans or air conditioning:

  • Spend the hottest part of the day somewhere cool.
  • Open windows at night and close your blinds during the day to retain the night’s cooler air.
  • Cool off under a wet towel and spray cool water on your skin.
  • Choose foods you can grill or eat cold—don’t bake or boil.
  • Don’t eat large or protein-rich meals—they warm your body from within.
  • Avoid dehydrating alcohol and caffeine.

If you go outdoors:

  • Wear lightweight, light-colored, loose-fitting clothing and a wide-brimmed hat.
  • Spend time in air-conditioned public buildings— malls, museums, and libraries, or in cooling centers
  • Use a sunscreen of SPF 30 or more.
  • Drink extra fluids, even if you’re not thirsty.

After recovery from heat stroke, many people are more sensitive to high temperatures for a while. So survivors should avoid hot weather and heavy exercise until their doctor says it’s safe to resume normal activities.

Stay cool, everyone.



Last Updated: September 2, 2020
Originally Published: September 1, 2014