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Heat Related Illness

What is heat-related illness?

The heat of the sun can cause illnesses that range from unpleasant feelings to life-threatening heat stroke. According to the National Weather Service, about 175 Americans succumb to the demands of summer heat in a normal year. When it is dangerously hot, be alert for the signs and symptoms of heat stroke and heat exhaustion and take special care to protect infants, children, the sick and the elderly from the hazards of summer heat.

How hot is "dangerously hot"?

The risk of heat illness is present when the heat index is 100 °F or more. The heat index is an accurate measure of how hot it really feels when relative humidity is added to the actual air temperature. For example, if the temperature is 90 °F and the humidity is 60 percent, the heat index is 100°F. A temperature of 95 °F with relative humidity at 40 percent produces a heat index of 101 °F. When the heat index is this high, several illnesses such as heat stroke, heat cramps or heat exhaustion are possible with physical activity or prolonged exposure. The heat may overcome the body's ability to regulate internal body temperature at a safe level.

How can heat-related illness be prevented?

Good judgment and some simple precautions will help avoid possible dangers related to the heat:

  • Remain  indoors in an air-conditioned room during hot temperatures. If your home is not air conditioned, try to spend the hottest hours of the day in a cool public place such as a library, movie theater, or store.
  • When in a closed space such as a car or house without air conditioning, open windows for ventilation. Never leave children or pets in a parked car.
  • Avoid excessive physical exertion in hot temperatures, especially in the middle of the day. Take frequent rest periods in a cool, shady place during activity.
  • Drink extra fluids, preferably at least eight ounces of water or diluted fruit juice each hour. Alcohol and beverages with caffeine don't count. They can make the heat's effects on your body worse.
  • Wear light-colored, loose, lightweight clothing to reflect heat and allow air to circulate around the body. Wear a broad-brimmed hat in the sun.
  • Eat small meals and eat more often. Avoid foods that are high in protein, which increase metabolic heat and water loss.
  • Do not take salt tablets unless specified by a physician.
  • Click here for a list of medications and products that increase the risk of heat-related illness

Exactly what is heat stroke?

Heat stroke is a medical emergency that can cause convulsions, unconsciousness, and even death. It can occur in a short period of time when an individual is exposed to direct sunlight, poor air circulation and high temperatures, especially during physical activity. Possible signs of heat stroke are hot, dry flushed skin, rapid pulse, faintness, dizziness, headache, nausea, loss of consciousness, body temperature rising fast to 105 or higher, an absence of sweating, and muscle twitching or convulsions. If these symptoms occur, call an ambulance immediately. Treatment must be given at once. Until an ambulance arrives, place a blanket soaked in cold water over the victim. Never attempt to give water to an unconscious victim.

What is heat exhaustion?

Heat exhaustion is a milder form of heat-related illness than heat stroke and is not usually fatal. It takes hours or days to occur and results from loss of water and salt. Alcohol, lack of water, excessive sweating, vomiting and diarrhea can increase a person's chances of heat exhaustion. The signs and symptoms of heat exhaustion can include cool, clammy, pale skin, weakness, dizziness, blurred vision, headache, profuse sweating, shallow breathing, confusion, nausea, and mild muscle cramps before the attack. If heat exhaustion occurs, take immediate actions to cool the victim. Move the victim to a cool place. Apply cool, wet cloths to the forehead and wrists. Loosen clothing so air can circulate to the skin. Give the victim plenty of cool water to drink. If the victim does not respond to treatment within five to ten minutes, call an ambulance.

What are heat cramps?

Heat cramps are painful spasms that usually occur in the muscles of the legs or abdomen, usually accompanied by heavy sweating. If heat cramps occur, apply firm pressure on cramping muscles, or use gentle massage to relieve spasm. Get the person to a cooler place and have him or her rest in a comfortable position. Give the victim sips of water.

What to do and who to call if you are suffering from a heat related illness?

Call 911 for immediate medical assistance if you believe you or another person is experiencing heat stroke. Symptoms include body temperature above 103 degrees Fahrenheit; red, hot and dry skin without sweating; rapid, strong pulse; throbbing headache; dizziness; nausea; confusion; and loss of consciousness.

While waiting on emergency assistance, get the victim to a shady area, cool them rapidly using cool water and monitor body temperature until it reaches 101 to 102 degrees Fahrenheit, and do not give the victim any fluids to drink.

Additional Assistance

If a person is feeling sick after being exposed to the heat or has general health related questions, tell the individual to call their doctor’s office or their county health department for information. For a complete listing, click here .

If you are in need of a fan or air conditioner and cannot afford to buy one, contact your county Low Income Home Energy Assistance Program agency. For a listing, click here.