Knowing the Signs of Heat Exhaustion

Warm weather is one of the reasons that so many people look forward to the summer months. However, extreme heat can also be hazardous to your health. The human body sweats in order to cool itself down, but there are times when the body is exposed to high temperatures for long periods of time and the body is unable to regulate its temperature quickly enough. In these cases, heat exhaustion is a very real possibility.

Heat exhaustion occurs most often when you fail to replace the fluids you lose through perspiration and it is a very serious condition that requires immediate medical attention. If left untreated, heat exhaustion can quickly become heat stroke, a potentially fatal condition. It is important to recognize the signs and symptoms of heat exhaustion in order to determine the best course of action in terms of treatment. Heat exhaustion and heat stroke often progress rapidly, so time is of the essence.

 Symptoms of heat exhaustion often include:

– Feeling faint, dizziness

– Excessive perspiration

– Rapid heartbeat

– Drop in blood pressure

– Nausea or vomiting

– Cramping

– Thirst

– Headache

– Fatigue

– Clammy, pale skin

– Low fever

At the first signs of heat exhaustion, get the person out of the heat and into a cooler place as soon as possible and have them lay down. Elevate their feet by propping them up with a pillow or something similar. Provide fluids and monitor the person closely.

Certain individuals are more at risk to suffer from heat exhaustion. Children under 5 years of age, the elderly, pregnant women, the obese, those suffering from illnesses such as cardiovascular illness, respiratory disease, and hypertension and those who are on medications that affect the brain such as tranquilizers, antidepressants, or antihistamines. As a general rule, anything that can cause dehydration like drinking alcohol and  physical exertion in extreme temperatures can cause heat exhaustion.

The best way to avoid heat exhaustion is to keep drinking fluids, particularly fluids like Gatorade that replace electrolytes as well as fluid. Whenever possible, stay indoors and out of the heat on extremely warm days and wear appropriately light clothing. In the long term, those who exercise regularly are less vulnerable to heat exhaustion as their body’s cooling system functions more efficiently. So getting into a workout regimen (one that your doctor approves) can prevent you from suffering from heat exhaustion.


Wendy Bumgardner. Heat Illness – Definitions and Warning Signs. June 19, 2008.

American Institute for Preventative Medicine. Heat Exhaustion & Heat Stroke.

Jane Seegal. The Center for Construction Research and Training. Hazard Alert: Heat Stress in Construction.