What are the first signs of heat exhaustion? Here is what to keep an eye out for.

Each year, around 1,300 people die in the United States as a result of extreme heat-related illnesses, according to the Environmental Protection Agency.

Heat-related illnesses can range in severity but each should be taken seriously. From heat cramps to heatstroke, there are many conditions that can occur because of prolonged exposure to hot, humid weather. One of these is heat exhaustion.

If not treated properly, heat exhaustion can lead to life-threatening complications. It is important to recognize its symptoms to receive proper care. Here are the signs of heat exhaustion.

What is heat exhaustion?

Heat exhaustion is one of several heat-related illnesses. According to the Center for Disease Control and Prevention, heat-related illnesses include:

• Heat cramps
• Heat rash
• Heatstroke
• Rhabdomyolysis
• Heat syncope

All of these conditions can occur when your body overheats. This can be caused by exposure to hot temperatures, especially if it is humid or you are engaging in physical activity, according to the Mayo Clinic.

Your body's temperature is impacted by its environment. Your's body heat in relation to the environment's temperature is called "core temperature," according to the Mayo Clinic. The human body tends to remain at a core temperature of 98.6 degrees Fahrenheit.

Your body regulates temperature by sweating. When it is very hot outside, you are likely to sweat more since your body is trying to cool down. But if you are sweating excessively, this is not effective for maintaining homeostasis.

When you sweat, you lose fluids containing water, nutrients and salts that help you function properly. If you are not sufficiently replacing those lost fluids, you may experience a series of conditions, including dehydration or heat exhaustion.

Anyone can experience heat exhaustion. However, it can be impacted by other factors, such as age, alcohol use, medications or health conditions.

Older people and children are at higher risk of heat exhaustion since they are more likely to become dehydrated and often cannot regulate body temperature efficiently.

If you are drinking large quantities of alcohol, you also have a higher chance of heat exhaustion. When you are drinking, you can become dehydrated, which can lead to heat exhaustion. Alcohol also makes body temperature regulation harder, according to the Cleveland Clinic.

Some medications may trigger heat exhaustion if they lead to excessive loss of fluids, such as diuretics. Pre-existing conditions that lead to fluid loss, such as diabetes causing frequent urination, increase the risk of heat exhaustion.

What are the first signs of heat exhaustion?

According to the Mayo Clinic and Cleveland Clinic, heat exhaustion symptoms include:

• Dizziness, lightheadedness, feeling faint
• Headache
• Fever of 100 degrees Fahrenheit
• Fatigue
• Nausea
• Muscle cramps
• Excessive sweating
• Cool, clammy skin with goosebumps
• Swollen extremities (feet, hands, ankles)
• Rapid heartbeat

How to treat heat exhaustion

According to the CDC, to treat heat exhaustion, you should move to a cool place. If you are wearing tight clothing, remove it and loosen other garments.

It is important to hydrate with water. You can also put wet cloths on your body to cool down.

If your symptoms worsen or last longer than an hour, you should seek medical attention. If you also begin to vomit, get help.

If not treated properly, heat exhaustion can lead to heatstroke, which is a life-threatening condition.

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Want to learn more about dehydration and heat-related illnesses?

• Can dehydration cause dizziness? Here's what to know.
• Can dehydration cause fever?What to know about dehydration and symptoms to watch for.
• Can dehydration cause nausea? Get to know the condition's symptoms, causes.
• How to treat dehydration: What to do if you are dehydrated, according to an expert
• How long does heat exhaustion last? What to know about the heat-related illness.
• What is heatstroke? Symptoms and treatment for this deadly heat-related illness