Signs of Heat Illness

Heat illness progresses from mild to serious and can be dangerous, even life-threatening. Knowing the signs can be especially helpful for those who care for children and older adults. Heat illness can happen with exposure to heat, even if not exercising. And, taking certain medications such as psychotropics, medications for Parkinson’s, tranquilizers and diuretics may increase the risk of heat illness.

Stages, Signs and Treatment of Heat Illness

Extended time in heat and humidity and lack of adequate fluids can cause heat illness. Children, teens and the elderly (over age 65) are more sensitive to heat because their bodies don’t adjust as quickly to environmental changes as adults younger than age 65. Here’s how to recognize heat illness:

Type of Heat Illness




Heat cramps (mildest form)

  • Intense exercise in high heat
  • Painful cramps or muscle spasms most common in legs
  • Flushed, moist skin
  • Stop activity and rest in a cool place
  • Take off extra clothing and apply cool cloths to skin
  • Drink fluids that contain sugar and salt
  • Slowly stretch cramped muscles

Heat exhaustion

  • Loss of water and salt
  • Extreme heat and sweating without fluid and salt replacement

Same as above, plus:

  • High fever (over 100.4)
  • Headache
  • Nausea/vomiting
  • Diarrhea
  • Weakness/fatigue
  • Anxiety

Same treatment as above; if no improvement or fluids won’t stay down, go to the emergency room.

Heat stroke (life threatening)

  • Body is overwhelmed by excessive heat and doesn’t properly regulate the heat

Same as above, plus:

  • Rapid heart rate
  • Lack of appetite
  • Confusion or agitation
  • Stupor or lethargy
  • Seizures

Begin same treatment as above and call 911 or go to emergency room. In the meantime, place ice bags in armpit and groin area.


How to Avoid Heat Illness

Follow several guidelines to avoid starting down the path of heat illness:

  • Watch the heat index - if over 90 degrees Fahrenheit, heat exposure is riskier.
  • Understand if your child’s health issues (including obesity) or medication make him or her more susceptible
  • Beware of the need for extra hydration and breaks from the heat when wearing heavy clothing such as for football or band practice (if wearing heavy uniforms)
  • Stay hydrated and encourage your children to drink fluids even if they don’t think they’re thirsty.
  • Dress in lightweight, lightly-colored clothing.
  • Take breaks from activity to cool off in air conditioning, with a cool bath or in a swimming pool.
  • Talk with coaches and/or camp counselors about policies regarding heat illness prevention.

Finally, remember to never, ever leave children or animals in a closed vehicle, even for a short time. Inside car temperatures can increase by as much as 19 degrees in as little as 10 minutes. Closed vehicles can be life-threatening.



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