Feeling off in the heat? Here’s how to spot symptoms of heat exhaustion.
Summer days outdoors should leave you feeling recharged, not wiped out. But when temperatures soar, your body sometimes can't keep pace. Those moments when you feel dizzy, queasy, or just not quite right in hot weather? That's not something to ignore. You might be experiencing early symptoms of heat exhaustion, a condition that develops surprisingly fast and can take a serious turn if you miss it.
Whether you're working outside, exercising in the sun, or just stuck in a heatwave, it's important to know what heat exhaustion feels like and when to get help. In this guide, we’ll walk you through what heat exhaustion actually is, the key symptoms to watch for and who’s most at risk when temperatures rise.
Knowing what to look for helps you protect yourself and spot when someone else might be in trouble, too.
What exactly is heat exhaustion?
Heat exhaustion happens when your body overheats and can’t cool itself down fast enough. This is usually due to high temperatures, humidity and physical activity. It’s your body’s warning sign that it’s struggling to keep your internal temperature in a safe range.
Under normal conditions, sweating keeps you cool as moisture evaporates from your skin. The problem starts when extreme heat or humidity makes this process ineffective. As your body loses water and essential salts faster than you can replace them, it throws off everything from blood pressure to energy levels.
While heat exhaustion isn't as immediately dangerous as full-blown heatstroke, it's definitely not something to brush off. Without intervention, it can rapidly progress to a medical emergency.
This is why recognizing those early warning signs (and actually responding to them) makes such a difference in preventing serious complications.
Not feeling right? Here are the most common symptoms of heat exhaustion.
Heat exhaustion can sneak up on you. Maybe you're going about your business: working in the yard, taking that beach hike, or cheering at your kid's soccer tournament. Then things suddenly feel “off.”
The transition from "I'm fine" to "Something's definitely wrong" can happen surprisingly fast.
If you're in hot weather and start feeling unusual, watch for these telltale symptoms of heat exhaustion:
- Heavy sweating
- Cool, pale, or clammy skin
- Dizziness or feeling lightheaded
- Fatigue or sudden weakness
- Headache
- Nausea or vomiting
- Muscle cramps
- Fast or weak pulse
- Fainting or feeling like you might pass out
If you notice any of these symptoms (especially after being in the heat), be sure to act quickly. Move to a cooler place. Drink water or a sports drink and rest.
If symptoms do not improve within 30 minutes or if they worsen, seek medical attention immediately. Signs of heat stroke—such as confusion, extreme fatigue, neurological symptoms, seizures, or loss of consciousness—require emergency care and should be treated in the Emergency Department without delay.
Who needs to be extra careful in the heat?
Heat exhaustion can affect anyone, but some people are more at risk, especially during heat waves or long stretches outside.
You may be at higher risk for heat exhaustion if you:
- Are over 65 or a young child
- Have chronic conditions like heart disease, diabetes, or high blood pressure
- Take certain medications that affect how your body regulates heat (like diuretics or antihistamines)
- Work or exercise outdoors for long periods
- Aren’t used to hot weather or haven’t acclimated to rising temperatures
- Are dehydrated or haven’t been eating enough salt and fluids
If you or someone you’re with starts showing symptoms of heat exhaustion, it’s important to take them seriously. Acting quickly can help you cool down, feel better and avoid more serious complications like heatstroke.
Feeling off in the heat? Don’t wait it out.
If you’re experiencing symptoms of heat exhaustion and aren’t feeling better after cooling down and hydrating, stop by your nearest CityMD. Our providers are here to help; no appointment needed.
We’re ready to care for you.
Visit any CityMD urgent care location in your community today for an evaluation with one of our expert providers.