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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medically reviewed by WellAlly Editorial TeamLast reviewed October 19, 2026Editorial policy
First Aid18 min read

First Aid for Heat Exhaustion

Published: October 19, 2026Updated: October 19, 2026

Heat exhaustion occurs when the body overheats and loses critical fluids and salt through excessive sweating, typically during strenuous activity in high temperatures. If not addressed quickly, it can progress to heat stroke, a life-threatening medical emergency. Prompt first aid involving rapid cooling, rest, and electrolyte replacement is essential for recovery.

Quick Summary

Move the person to a cool, shaded environment, loosen tight clothing, apply cool damp cloths, and provide slow sips of water or an electrolyte solution.

Important Medical Disclaimer

This guide is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult with qualified healthcare providers for medical concerns.

Step-by-Step Guide

1

Move to a Cooler Environment

Immediately relocate the person out of direct sunlight or hot conditions into an air-conditioned building or deep shade. Have them lie down and rest quietly to lower their metabolic heat production. If they feel dizzy or lightheaded, elevate their feet slightly above heart level to improve circulation to the brain.

Important: Do not leave the person unattended in an enclosed, unventilated space or vehicle.

2

Loosen and Remove Excess Clothing

Remove heavy, tight, or restrictive garments such as jackets, shoes, socks, and hats. Exposing as much skin as possible allows trapped body heat to escape and facilitates sweat evaporation. Ensure good air circulation by using a fan or positioning the person in a natural breeze.

3

Actively Cool the Body

Place cool, damp cloths or ice packs wrapped in towels on areas where large blood vessels lie close to the skin, including the neck, armpits, and groin. You can also spray or mist the skin with cool water while continuously fanning them to accelerate evaporative cooling. A cool sponge bath or soaking hands and forearms in cool water are also effective methods.

Important: Do not use an ice bath or extremely cold water for heat exhaustion, as intense shivering can paradoxically raise core body temperature.

4

Provide Rehydrating Fluids

Offer cool water, oral rehydration salts, or an electrolyte-rich sports drink to restore lost volume and essential minerals. Encourage the person to drink slowly in small, steady sips rather than gulping down large amounts at once. Avoid very cold drinks, which may cause stomach cramps.

Important: Never force fluids or give drinks to someone who is vomiting, disoriented, or losing consciousness.

5

Rest and Monitor for Improvement

Keep the person resting comfortably and observe their symptoms closely for 30 to 60 minutes. Look for gradual improvements such as a slowing heart rate, clearing of dizziness, and reduced nausea. They should not resume physical activity or return to the heat for the remainder of the day.

6

Recognize Warning Signs and Call Emergency Services

Heat exhaustion can rapidly transition into heat stroke, which requires immediate advanced medical care. Call 911 or your local emergency number if the person develops altered mental status, confusion, slurred speech, seizures, or persistent vomiting. Continue aggressive cooling efforts until professional emergency personnel arrive.

Important: If symptoms do not begin to improve within 30 to 60 minutes despite cooling measures, seek immediate medical evaluation.

Frequently Asked Questions

What is the key difference between heat exhaustion and heat stroke?
Heat exhaustion typically involves heavy sweating, weakness, nausea, and normal mental function with a body temperature below 104°F (40°C). Heat stroke is a medical emergency marked by a core temperature of 104°F or higher and severe neurological symptoms like confusion, delirium, seizures, or unconsciousness.
How long does it take to recover from heat exhaustion?
Most mild symptoms improve within 30 to 60 minutes of cooling and resting, but full physiological recovery generally takes 24 to 48 hours. Avoid strenuous exertion and excessive heat exposure during this recovery period, as susceptibility to recurrent heat illness remains high.
Should someone with heat exhaustion take salt tablets?
No, salt tablets should not be used. Concentrated salt can irritate the stomach, trigger vomiting, and worsen dehydration; drinking a standard oral rehydration solution, sports beverage, or water with light snacks is much safer and more effective.
Who is at the highest risk for developing heat exhaustion?
Infants, young children, older adults, and outdoor workers or athletes are at highest risk. Additionally, people with heart disease, high blood pressure, or those taking medications like diuretics, antihistamines, or beta-blockers have a reduced ability to regulate body temperature.
  1. 1
    CDC - Heat Stress: Heat-Related IllnessesSource
  2. 2
    Mayo Clinic - Heat Exhaustion: Symptoms and CausesSource
  3. 3
    NHS - Heat Exhaustion and HeatstrokeSource
  4. 4
    UpToDate - Exertional Heat Illness in Adolescents and AdultsSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed October 19, 2026. · Read our editorial policy