Summers keep getting hotter, and staying comfortable in the heat is only part of the challenge. The bigger concern is stopping the body from overheating in the first place, since that overheating can progress from a milder condition called heat exhaustion into the far more dangerous heat stroke. Knowing the warning signs of both can help you protect yourself, your friends and your family.
How the body fights back against heat
Heat stroke is a serious condition that can lead to seizures, organ failure and more. Before someone reaches that point, they typically pass through a milder stage known as heat exhaustion. Both conditions occur when the body overheats. Normally, the body cools itself by moving warm blood from the core to the surface of the skin, where that heat radiates out into the surrounding environment. Sweating helps too, since the evaporation off the skin has a cooling effect. Trouble starts when the environment itself is too hot or too humid for either of these cooling mechanisms to keep up.
Who is most at risk
In otherwise healthy people, heat stroke is often tied to exercise, since physical activity raises the body's core temperature on its own. That risk climbs further for anyone who isn't very fit, or who is used to working out in cooler weather. Over time, as the body becomes accustomed to exercising in heat, it gets better at cooling itself efficiently.
Several factors raise the risk of both heat exhaustion and heat stroke:
- Exercising in high temperatures and humidity
- Poor fitness
- Being large, regardless of body type, since both excess fat and excess muscle affect the body's ability to cool down
- Dehydration
- Wearing or carrying gear, such as football pads or a hiking pack
- Drinking alcohol
- Using certain medications or supplements, including beta blockers and diuretics, so it's worth checking the information that came with any medication
- Any disability or illness that makes it harder to get out of the heat or to cool down
Spotting heat exhaustion
Heat exhaustion sets in when the body's core temperature rises, but not high enough to affect the brain. If you or someone overheated shows any sign of confusion, treat it as heat stroke immediately and get medical help right away.
According to the CDC, signs and symptoms of heat exhaustion can include:
- Dizziness
- Nausea and vomiting
- Headache
- Fatigue or weakness
- Heavy sweating
- Cold, pale and clammy skin
- A fast, weak pulse
If these symptoms appear, start cooling down immediately: move to shade or air conditioning, loosen clothing, drink something cold, and keep watching for any sign of things getting worse instead of better. If there's no improvement within an hour, seek medical help.
Recognizing heat stroke
Heat stroke occurs when the body's temperature becomes extremely high, over 104 degrees when taken rectally, and it can affect the brain as well as the rest of the body. A person suffering from heat stroke may be too confused to even realize they're in danger, which makes it critical for the people around them to watch for warning signs.
Heat stroke is a serious medical emergency, so get help immediately if you suspect it. At an event with medical staff on site, such as a marathon or a football game, alert them right away. Otherwise, call 911 or the emergency number for the area. Along with symptoms like headache, dizziness and nausea mentioned above, heat stroke can also involve:
- Confusion, irritability or hallucination
- Passing out or collapsing
- Trouble walking
- Seizures
- Reddened skin, with or without sweating
Cooling someone down while help is on the way
While waiting for help to arrive, you can start cooling the person down. Medical staff may decide it's best to cool the person before transporting them to a hospital, though that depends on whether other medical treatment is needed first. The ideal way to cool someone with heat stroke is to place them in a tub of cold water with ice, stirring the water constantly.
If that isn't possible, a cold shower or a cold hose can work, or ice-cold wet towels can be applied to the person's body. Swap the towels out every three minutes, or whenever they stop feeling icy cold.
