The dog days of summer are upon us. It’s a time when many of us go outside to have fun, but spending time outside in extreme heat can cause heat-related illness and, in severe cases, heat stroke. Our experts provide guidance on understanding how to prevent, recognize and treat it.
What is heat stroke?
This is the most severe form of heat-related illness. It occurs when your body overheats due to prolonged exposure to high temperatures or intense physical activity in hot weather, and it can happen in minutes or over hours or days. When it happens, your body temperature may rise to 104 degrees or more. Take caution if the outside temperature is over 77 degrees, and consider over 85 degrees to be dangerous. Even on cloudy days, high temperatures can cause heat stroke.
There are two primary types:
- Exertional heat stroke affects people who are active outdoors in hot conditions, such as athletes, laborers, or first responders. Strenuous exertion and heat can overwhelm the body’s cooling system.
- Non-exertional (classic) heat stroke affects vulnerable populations, such as older adults, young children, or people with chronic illnesses. It can occur without physical exertion, particularly during heat waves.
How to prevent heat stroke
Here are some ways you can help yourself stay safe during hot weather:
- Drink plenty of fluids, especially when outdoors. Avoid caffeinated or alcoholic beverages.
- Wear lightweight, loose-fitting, and light-colored clothing.
- Limit outdoor activities during the hottest parts of the day, typically between 10 a.m. and 4 p.m.
- Take frequent breaks in the shade or cool areas if outdoors.
- Sunburn can affect your body’s cooling ability, so use sunscreen.
- Check with your doctor to see if any medications you use can increase the risk of heat stroke.
Recognizing the symptoms
Early treatment for heat stroke can be the difference between life and death. If you recognize any of the following symptoms in yourself or someone else, get immediate medical attention:
- Core body temperatures of 104 degrees or higher are the main sign of heat stroke. You may need a rectal thermometer because other types may not be accurate in heat stroke.
- You may become confused and agitated, slur your speech, be irritable, delirious, suffer seizures, or lose consciousness.
- For classic heat stroke, your skin may feel hot and dry. In exertional heat stroke, your skin may feel moist. Either way, it’s a sign that your sweating mechanism is not cooling your body.
- You may feel sick to your stomach, nauseous, or vomit, which can contribute to dehydration.
- Your skin may turn red and flushed as your body temperature rises.
- Heat stroke makes your heart work harder to cool your body so you may breathe rapidly and have a strong pulse.
How to treat it?
If you think someone near you is experiencing heat stroke, here’s what you should do:
- Call emergency services. This is a medical emergency requiring quick intervention, so call 911 immediately.
- Move to a cooler place. Get out of the sun and into a shady or air-conditioned location.
- Cool their body. Apply cool water to the skin with a sponge, garden hose, or wet towel. Use ice packs or cold, damp cloths on the armpits, groin, neck, or back, where blood vessels are closest to the skin and cool the body more quickly.
- Use a fan. A fan increases cooling by moving air that helps evaporate water from the skin.
- Hydrate carefully. If the person is conscious and can drink, give them cool water or a sports drink. Do not use caffeinated beverages or alcohol, as these can increase dehydration.
- Monitor symptoms. Keep a close watch on the person until emergency medical help arrives.
The next time you are making plans to go outside on a hot day, make a plan for staying cool and hydrated to stay safe. If you recognize symptoms in yourself or others, seek medical help immediately. Click here to learn about emergency medical care at Luminis Health.
Author
![](/sites/default/files/Gillian-Lowe-2.jpg)
Gillian Lowe, MD is a primary care provider at Luminis Health.