by Rebecca Mikulin

Created on: July 29, 2011   Last Updated: July 30, 2011

Heat stroke is a very serious and potentially deadly condition that may strike during the summer, especially in humid areas. It is important to note that heat stroke and heat exhaustion are not the same thing, though some lay people may use the terms interchangeably. Heat exhaustion may progress to heat stroke, and the signs of heat exhaustion are a warning that you need to get measures to cool off and re-hydrate immediately. Heat stroke, on the other hand, is a medical emergency and must be tended to immediately. Untreated heat stroke can lead to organ damage, including brain damage, and possibly death.

Heat Exhaustion Symptoms

As the precursor to heat stroke, heat exhaustion is considered the most clearly-identifiable warning sign of heat stroke. These may occur during exercise, especially in hot weather, or they may be the result of extreme heat exposure without any exercise.

The most recognizable signs are excessive sweating, flushed face, headache, nausea, dizziness, and a fast heartbeat. You may also notice darker-colored urine, which is associated with dehydration. These symptoms can range from a dull, throbbing headache and minor dizziness to almost flu-like symptoms. You must get out of the heat or stop exercising immediately and find a way to cool off before it progresses to heat stroke.

Signs of Heat Stroke

Especially if someone has felt the effects of heat exhaustion before, it may be difficult to pinpoint when exactly it is considered heat stroke instead. The most measurable sign is if you’re running a fever of 104 degrees Fahrenheit or more. If you do not have a thermometer available, but are unable to cool off after about a half an hour in a cool area, seek medical attention.

People with heat stroke often experience severe, stabbing headaches, darkened vision, dizziness severe enough to impair normal movement, disorientation, or loss of consciousness. In many cases, a person with heat stroke will be unable to drink water, and may be hyperventilating. If you stop sweating in extreme heat or during heavy exertion, you are likely suffering from severe dehydration and may develop heat stroke very quickly after that. These are all signs that the person must be moved to a cool location immediately, misted with cool water or covered with wet sheets, and emergency services must be contacted.

A doctor will be able to monitor the cooling to ensure that it’s not done too quickly or to a dangerous point, as well as ensure that fluids are properly administered. Many people with heat stroke will require intravenous fluids, as well as careful assessment and monitoring to try to prevent damage to major organs.

Preventing Heat Stroke

The best way to prevent heat stroke is to behave sensibly in extreme heat, as well as during heavy workouts. When it’s hot out, dress appropriately – wear a hat and light, loose clothing, always have water readily available, and avoid alcohol and caffeine. Limit exertion in the heat of the day, and stay indoors where it’s cool whenever possible. In addition, if you’re sweating a lot, make sure to drink beverages formulated for sports (i.e. Gatorade, Powerade) or eat fresh fruit in order to help replenish the electrolytes lost through excessive sweating. Sodium and potassium are depleted through sweat and hot-weather exertion, and must be replenished in order to avoid heart failure. Heat stroke is a very serious condition, but with just a few precautions it can be avoided in hot weather.

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