Signs of Heat Stroke

Man drinking water on hot day to avoid heat stroke
Compassionate Eye Foundation/Katie Huisman/Getty Images

Whether you are a parent, a caregiver or an athlete, it is important to know the signs of heat stroke.

Heat stroke is different from the type of stroke that affects the brain -a cerebrovascular accident- despite the similar name. Heat stroke is a condition in which the body temperature becomes so high that damage to the whole body, including the brain, occurs. Heat stroke is always a medical emergency because it can cause death.

Who gets heat stroke?

Heat stroke can affect anyone, but young children, teenagers and the elderly are most susceptible.

Healthy young adults who participate in athletic training or tanning in hot temperatures can develop heat stroke. Often, young athletes do not notice the initial symptoms, do not know to look out for them or are too embarrassed to complain about discomfort in an athletic training or tanning setting.

Young children, the elderly and even young adults often do not know how to prevent heat stroke or how to recognize or ask for help when they have heat stroke. So learning about heat stroke can help save the ones you care about if they are unable to care for themselves.

What is heat stroke?

Heat stroke is a dangerous health condition that requires emergency medical attention. Knowing the causes of heat stroke can help prevent it from happening. Learning to recognize the signs of heat stroke can prevent a heat stroke from causing serious damage.

A heat stroke may occur when the body temperature is too hot – especially when body temperature reaches 104 degrees Fahrenheit or higher. The body becomes unable to sustain normal functions at very high temperatures. This is called hyperthermia. Heat stroke can occur when the temperature of the environment is very hot, either indoors of outdoors.

When the heat overwhelms the body’s normal ability to regulate temperature, a heat stroke can occur.

Dehydration, which is a lack of ideal body fluids and electrolytes, can intensify or speed up the heat stroke. When people exercise, the body creates heat. If the body produces heat when the body temperature is already too high from the environment, heat stroke can occur.

Warning symptoms:

Before a heat stroke, some warning signs include fatigue, dizziness, headaches, weakness, nausea, vomiting and cramps. Usually at this stage, often called heat exhaustion, if symptoms are treated promptly, it is unlikely to cause serious long-term consequences.

Treatment includes moving to a cooler temperature or using ice packs or cold material to cool down the body, drinking moderate amounts of non-caffeinated beverages and resting.

Heat stroke symptoms:

Heat exhaustion may progress to heat stroke, especially if it is untreated. Additionally, sometimes heat exhaustion progresses too quickly and may go unnoticed.

Symptoms include confusion, disorientation, collapsing, and loss of consciousness, seizures, trouble breathing, a rapid heart rate, hallucinations and lack of sweating.

Treatment at this stage requires trained medical professionals. An emergency team must be called immediately. While waiting for emergency personnel to arrive, it is important to move the patient to a cooler location and try to cool the body with ice packs or water.

Often, those who are susceptible to heat stroke are the least likely to ask for help. Some common settings of heat stroke:

  • Babies or young children left in a hot car. Parents or babysitters might underestimate the time and leave sleeping children in the car for convenience. The solution- It is NEVER safe to leave a child in the car.
  • The elderly or sick. Elderly people with weakened health may avoid turning on the air conditioning or a fan in hot weather, to save money or due to discomfort from blowing air. Some apartment buildings and homes are not equipped with air conditioners or air conditioning units. Many elderly people also avoid opening windows for safety reasons. The solution- An easy-to-use fan with several settings for comfort and a reliable thermometer to gauge temperature should be available.
  • Young adults training for sports. Young adults who have trained before may assume that they can always do what everyone else is doing. Lack of proper rest, lack of proper hydration, lack of proper clothes and sometimes simply random reasons may contribute to heat stroke. This is especially common in mid-day training sessions that last for hours. The solution- Stay on top of your teenager’s activities. Maintain communication with coaches. Use YOUR OWN judgment as a parent and trust yourself.
  • Tanning. Indoor and outdoor tanning may consist of long sessions under high heat. Tanners often relax or fall asleep and therefore do not notice warning symptoms such as dizziness or headaches. Additionally, many people who regularly tan may also diet excessively and thus also do not maintain adequate nutrition, making them more susceptible to heat exhaustion and heat stroke. The solution- Maintain moderation in heat exposure and plan for proper hydration.
  • Outdoor workers. Many outdoor jobs such as construction go into full swing when the weather is warm. People who work outside in hot temperatures are often very task oriented, working hard and possibly forgetting to eat, drink, or notice physical signs of discomfort. The solution- Stay hydrated. Cool off by working in shade intermittently if possible. Take allotted breaks in shade if possible. Keep ice packs handy. If you are the supervisor, make sure your staff is able to take scheduled breaks in the shade and keep cool packs and cool drinks handy.


Harlan SL, Chowell G, Yang S, Petitti DB, Morales Butler EJ, Ruddell BL, Ruddell DM, Heat-related deaths in hot cities: estimates of human tolerance to high temperature thresholds, International Journal of Environmental Research and Public Health, March 2014

Simpson C, Abelsohn A., Heat-induced illness, Canadial Medical Association Journal, July 2012

Mazerolle SM, Pinkus DE, Casa DJ, McDermott BP, Pagnotta KD, Ruiz RC, Armstrong LE, Maresh CM, Journal of Athletic Training, September 2011

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