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Even In The Amazon Jungles, Treatment For Heat Exhaustion Is The Same As It Is Right Here At Home

August 23, 1999
Cedars-Sinai Medical Center
If you're going to be sitting in a metal boat on a sun-drenched lake an hour's hike from the Amazon River, it's a good idea to take along plenty of fluids and possibly a doctor or two.

LOS ANGELES (August 18, 1999) -- If you're going to be sitting in a metal boaton a sun-drenched lake an hour's hike from the Amazon River, it's a good idea totake along plenty of fluids and possibly a doctor or two.

"It's hot and very humid. It's hard to get a good evaporative cooling processgoing," says Mary L. Hardy, M.D., director of the Integrative Medicine MedicalGroup at Cedars-Sinai Medical Center, a program that integrates Western medicalpractice with botanical medicine, traditional Chinese approaches, acupunctureand other alternative therapies. Dr. Hardy has studied traditional healingsystems in Kenya and China, as well as in Peru. A board-certified specialist ininternal medicine, she journeyed into Peru five years ago with a group ofresearchers studying botanical medicine and traditional healing systems andpractices.

"It's not so bad in the jungle because you have a lot of shade but in this open,metal boat, we were all really sweating. On the hike back, one of the members, apharmacist I was hiking with, suddenly got very sick, was throwing up andappeared flushed. She was normally a very pale person so it was very clear thatshe had heat exhaustion. We had to quickly figure out how to take care of her sowe wouldn't have to carry her out."

One team member contributed a powdered sport drink and Dr. Hardy added oralrehydration salt from her emergency kit. "We made a salty drink and gave hersmall sips because if you give too much, the sufferer will throw it right backup. We moistened a bandana with water, added a little bit of lavender/peppermintoil to make it even a little bit more cooling, and put that on the back of herneck, along with one on her face. Then we fanned her. In about 15 or 20 minutes,she was able to walk again."

"For the trip down the Amazon, I had two medical kits," she says. "I still taketwo with me, one with natural medicines and one with pharmaceuticals, so thatI'm prepared for anything that comes along. Luckily, there's a physician not toofar from where we go, so if something really bad happens, we have backup."

Whether you plan to trek through the Peruvian Amazon or ride a bike on a sunnyday in Los Angeles, Dr. Hardy says preparing yourself ahead of time for the heatis the most important preventive measure you can take.

But if you're in the heat longer than expected, you're exercising beyond yourlevel of safety, or you have a medical condition that makes you susceptible,know the symptoms of heat exhaustion and take immediate action if needed.Failure to do so can push your body into heatstroke, requires professional,emergency intervention and can be fatal.


  1. Don't eat a heavy meal of high-fat foods.
  2. Do eat light foods that are easily digested. Include only small amounts ofprotein.
  3. Do drink plenty of water and a sport drink to be sure your fluids andminerals are in good shape before you leave home. Add a little vitamin C ordrink a glass of diluted fruit juice containing vitamin C to increase your levelof antioxidants, which help protect cells and muscles from damage.
  4. Avoid alcohol and caffeine, which can contribute to dehydration.
  5. Avoid carbonated beverages, which tend to be highly acidic and contain toomuch sugar.
  6. Wear loose, light-colored clothing that will help reflect the sun and allowperspiration on your skin to evaporate.
  7. Use and take along a sunscreen. Getting a sunburn will impair your ability todissipate heat.

Sweating is your body's natural attempt to maintain normal body temperature. Theevaporation of sweat cools your skin. Therefore, your two goals in avoiding heatexhaustion are to continually replace the fluids that are being lost throughsweat while optimizing conditions that allow sweat to evaporate. Humidityreduces evaporation, reducing your body's ability to cool itself. The use of afan can help increase evaporation.

Sweat contains minerals, including sodium, potassium and magnesium, that yourbody needs. But Dr. Hardy says many people make the mistake of replacing sweatwith water or juice that do not replenish these necessary nutrients. Shesuggests drinking a sport drink that contains about 100 milligrams of sodium andpotassium per serving and about 25 milligrams of magnesium per serving.Regardless of the exact amounts, most powders or pre-mixed sport drinks shouldbe adequate for routine activity.

She also recommends checking to be sure a sport drink contains a sugar source,such as glucose or fructose, and that it has vitamin C. "You might have a drinkthat contains about 100 or 200 milligrams of Vitamin C in it or you can mix yourdrink with fruit juice or put some vitamin C powder in it."

If you get into a situation where you're overheating and you don't have areplenishing drink handy, dilute some fruit juice with water and put a littlebit of salt in it, suggests Dr. Hardy. It should taste slightly salty.

Watch for the symptoms of heat exhaustion: The skin may become cool, moist, paleor flushed, accompanied by heavy sweating, headache, nausea or vomiting. You maybecome dizzy and exhausted to the point of collapse.

The elderly and people with pre-existing medical conditions are especiallysusceptible. Many disorders and medications to treat disorders can interferewith dissipation of heat. For example, diuretics, medications taken to increaseurine output, can decrease a patient's sodium level, complicating the effort tomaintain electrolyte balance. Antihistamines taken to counter allergies also cancause problems of fluid absorption and output.

Little children are at increased risk, too, says Dr. Hardy, because they can'tcomplain, their skin is very sensitive to sunburn, and they have a small bodymass, making it harder for their bodies to regulate heat. "You have to be realattentive and if the baby is more listless than usual, he or she may need somediluted apple juice with a little pinch of salt."

If heat exhaustion is not treated, it may lead to heatstroke: Your face will beflushed, skin will be hot and dry, and sweating will stop as body temperaturerises. Headache, nausea and dizziness will progress to confusion, delirium,shock, coma and even death. Emergency assistance should be called as quickly aspossible. If you're with someone who is suffering from heatstroke, soak thevictim in cool water if possible or wrap the victim in a cool, wet sheet in theshade while waiting for help to arrive.

According to Dr. Hardy, most of the symptoms of heat exhaustion and heatstrokeresult from three events. Excessive loss of fluid leads to a reduced amount ofblood circulating to your working muscles and the rest of your body, includingyour brain. Even a one percent loss of volume can begin to cause problems. A lowblood sodium level can lead to brain swelling and neurological symptoms. And lowmineral levels trigger muscle cramping and other physical symptoms.

"The sodium, volume and mineral depletion cause most of the symptoms and thenthe body's core temperature goes up," says Dr. Hardy. "Your regular ways to getrid of heat -- flushing and sweating -- are no longer effective and you'recrossing the border from

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Cite This Page:

Cedars-Sinai Medical Center. "Even In The Amazon Jungles, Treatment For Heat Exhaustion Is The Same As It Is Right Here At Home." ScienceDaily. ScienceDaily, 23 August 1999. <>.
Cedars-Sinai Medical Center. (1999, August 23). Even In The Amazon Jungles, Treatment For Heat Exhaustion Is The Same As It Is Right Here At Home. ScienceDaily. Retrieved May 17, 2024 from
Cedars-Sinai Medical Center. "Even In The Amazon Jungles, Treatment For Heat Exhaustion Is The Same As It Is Right Here At Home." ScienceDaily. (accessed May 17, 2024).

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