How Do I Know If I Had Heat Exhaustion?

Reviewed on 6/10/2022
Man working in a greenhouse wiping his sweaty forehead
Heat exhaustion symptoms include heavy sweating, muscle cramps, cold/pale/clammy skin, being very thirsty, fast and weak pulse, fast breathing, fatigue, weakness, dizziness, nausea, loss of appetite, headache, lightheadedness/fainting, and temperature of 100.4° F/38° C or above.

Heat exhaustion is a type of heat-related illness. 

You may have heat exhaustion if you have signs and symptoms such as: 

If not treated, heat exhaustion can lead to heat stroke (also called sun stroke), a life-threatening medical condition that occurs when the body's cooling system stops working and the body’s core temperature increases to a point at which brain damage or damage to internal organs can occur (105° F [40.5° C] or greater).

Seek immediate medical help if you experience: 

  • Worsening symptoms
  • Symptoms lasting more than one hour
  • Shortness of breath
  • Chest pain
  • Abdominal pain 
  • Inability to keep fluids down (vomiting
  • Deterioration of mental status (confusion or delirium)

What Causes Heat Exhaustion?

Heat exhaustion is caused by working, exercising, or playing in very hot and humid weather. 

Risk factors for developing heat exhaustion include: 

  • Inadequate fluid intake and dehydration
  • Wearing clothing that is too heavy, too many layers, or is dark-colored 
  • Direct sun exposure with no available shade
  • Alcohol consumption 
  • Being overweight or obese
  • Low fitness level
  • Low potassium levels (hypokalemia
  • Lack of acclimatization to the heat
  • Wearing sports equipment such as heavy pads or helmets
  • Age (toddlers and young children and the elderly are more susceptible) 
  • Fever
  • Use of certain medications
    • Stimulants 
    • Diuretics 
  • Lack of sleep
  • Sickle cell trait

How Is Heat Exhaustion Diagnosed?

  • Heat exhaustion can be diagnosed with a patient history that includes being in a hot environment, a physical examination, and a temperature reading. 
  • Tests are not usually needed to diagnose heat exhaustion unless electrolyte imbalance or significant dehydration is suspected.

What Is the Treatment for Heat Exhaustion?

Treatment for heat exhaustion includes:

  • Move to a cool, shaded area or go into an air-conditioned building or car
  • Drink plenty of fluids 
  • Apply active cooling measures
    • Sit in front of a fan 
    • Take a cool shower or bath
    • Place a cold pack or cool compress on the neck, armpits, or groin
  • Remove excess clothing or tight clothing 
Reviewed on 6/10/2022
Image Source: iStock Images