Heat exhaustion occurs when your body gets too hot. The hypothalamus, the part of the brain that controls thirst and hunger, also controls the body's core temperature. Normally, the body cools itself by sweating. But if you are exposed to high temperatures for a long time (working outdoors in the summer, for example) and don't replace the fluids you lose, the body systems that regulate temperature become overwhelmed. As a result, your body produces more heat than it can release. Heat exhaustion requires immediate attention because it can progress to heat stroke, a life-threatening illness.
People with heat exhaustion may experience the following signs and symptoms:
If body temperature goes above 104°F, or if coma or seizure occurs, the patient may have heat stroke. Heat stroke can quickly lead to heart attack and death if not treated.
Heat exhaustion occurs most often when you are exposed to high temperatures and become dehydrated, usually from not drinking enough fluids. It also can happen when large volumes of sweat are replaced with fluids that don't contain enough salt.
The following factors increase the risk of developing heat exhaustion:
If you have symptoms of heat exhaustion, you should see a doctor immediately. The doctor will perform a physical examination, check your blood pressure, pulse, and temperature, and assess how dehydrated you are. The doctor may also request lab tests of blood and urine samples.
If you are working or exercising in the heat, don't wait until you get thirsty to drink fluids. Instead, drink plenty of fluids before, during, and after the activity. Take the following precautions to prevent heat exhaustion:
The primary treatment for heat exhaustion is to rest in a cool environment (a shady spot or, better, an air-conditioned room) and to drink cool (not icy) fluids. Water is usually enough to reverse dehydration, or you can drink a sports drink that contains electrolytes. You can also cool down by spraying yourself with water and fanning.
Your health care provider may recommend an oral or intravenous saline electrolyte solution.
Health care providers may recommend drinking fluids that contain electrolytes (see Prevention section). Endurance athletes may want to take mineral supplements including:
Foods high in these nutrients include dark leafy greens, nuts, seeds, whole grains, sea vegetables, blackstrap molasses, and bananas.
The most important treatment for heat exhaustion is replacing lost fluids by drinking water or a sports drink. Some herbs may help reduce body temperature, but if you have symptoms of heat exhaustion you should talk to your health care provider before taking anything. Although no studies have examined using herbs to treat heat exhaustion specifically, the following herbs may reduce fever or lower body temperature:
Although few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of fevers based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.
If you avoid heat stroke, recovering from heat exhaustion usually takes 24 - 48 hours. Depending on the severity of heat exhaustion, you may be hospitalized so doctors can monitor your fluid and electrolyte levels to avoid complications.
Your health care provider will want to check the fluid levels in your body to see if electrolyte replacement should be continued.
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