Heat-related illness

Heat-related illnesses (HRI) can be caused by spending too much time in the sun, exercising in a hot environment, taking certain medications and being in areas of high humidity. Anyone can suffer from HRI, but young children and the elderly are most at risk.

There are four generally recognized forms of HRI:

  • Heat cramps are painful muscle spasms — usually in the calves, thigh or stomach — after exercise. Treat by removing the patient from the heat, giving small amounts of water or sports drink, and gently stretching and massaging the muscles.
  • Heat exhaustion is recognized by headache, nausea, vomiting, dizziness or weakness after exercise. Profuse sweating and lightheadedness are also symptoms. Treat by removing the patient from heat, removing clothing and then spraying the body with cool water and then placing the patient under a fan. Give a small amount of cool water or sports drink.
  • Heat syncope is fainting from heat. Keep the patient flat and follow the same treatment for heat exhaustion.
  • Heat stroke occurs after prolonged physical exertion or prolonged exposure to high temperatures. Signs include mental confusion, rapid/weak pulse and hot/flushed skin. Call 911 for assistance. Then follow the same treatment for heat exhaustion BUT do not give liquids and do place ice packs in the arm pits, groin and on the neck.

To avoid all forms of HRI, don’t exercise in hot environments. Drink lots of fluid. Ensure adequate cooling, especially for the elderly and chronically ill. Gradually acclimate to exercise slowly and over time.

Heat-related illness can be caused by overexposure to the sun or any situation that involves extreme heat. Young children and the elderly are most at risk, but anyone can be affected.

Heat cramps

  • Symptoms include muscle spasms, usually in the legs and stomach area.
  • To treat, have the person rest in a cool place and give small amounts of cool water, juice or a commercial sports liquid. (Do not give liquids if the person is unconscious.)
  • Gently stretch and massage the affected area.
  • Do not administer salt tablets.
  • Check for signs of heat stroke or exhaustion.

Heat stroke and exhaustion

  • Symptoms of early heat exhaustion symptoms include cool, moist, pale or flushed skin; headache; dizziness; weakness; feeling exhausted; heavy sweating; nausea; and giddiness.
  • Symptoms of heat stroke (late stage of heat illness) include flushed, hot, dry skin; fainting; a rapid, weak pulse; rapid, shallow breathing; vomiting; and increased body temperature of more than 104 degrees.
  • People with these symptoms should immediately rest in a cool, shaded place and (if conscious) drink plenty of non-alcoholic, non-caffeinated fluids.
  • Apply cool, wet cloths or water mist while fanning the person.
  • Seek immediate medical attention by calling 911 or your local emergency number for symptoms that include cool, moist pale skin, rapid pulse, elevated or lowered blood pressure, nausea, loss of consciousness, vomiting and high body temperature.
  • For late stage heat stroke symptoms, cool the person further by positioning ice or cold packs on wrists, ankles, groin and neck and in armpits.
  • Administer CPR if the person becomes unconscious.

Content reviewed and edited by William Moore, MD, medical director of ETMC Emergency Medical Services.
Rev. 10-15-16