Hot weather dangers: Heatstroke vs. heat exhaustion

Posted: Updated:
PHOENIX (3TV/CBS 5) -

As the mercury rises, people need to make sure they are watching for heat-related illnesses, especially when the forecast calls for 115-120 degrees.

Let start with the basics.

What is heatstroke?

Heatstroke, or sunstroke, is the most serious form of heat injury and is considered a medical emergency. Heatstroke is the result of prolonged exposure to hot temperatures and usually combined with dehydration. This leads to the body not being able to regulate its internal temperature.

Signs of Heat Stroke include:

  • Throbbing headache, dizziness and light-headedness, lack of sweating despite the heat
  • Red, hot, and dry skin, muscle weakness or cramps, nausea and vomiting
  • Rapid heartbeat, which may be either strong or weak; rapid, shallow breathing
  • Behavioral changes such as confusion, disorientation, or staggering, seizures, unconsciousness

Heat stroke can kill or cause damage to the brain and other internal organs. If you see someone experiencing heat stroke, call 911 immediately.

What is heat exhaustion?

Again, this is a heat illness that occurs after you have had long periods of time out in the heat and usually are dehydrated. There are two types of heat exhaustion:

-Water depletion
Signs include excessive thirst, weakness, headache, and loss of consciousness

-Salt depletion
Signs include nausea and vomiting, muscle cramps, and dizziness.

Signs of heat exhaustion include:

  • Confusion, dark-colored urine (a sign of dehydration), dizziness
  • Fainting, fatigue, headache, muscle or abdominal cramps
  • Nausea, vomiting, or diarrhea, pale skin, profuse sweating, rapid heartbeat

If you feel you are experiencing heat exhaustion get out of the heat immediately and inside to an air conditioned area, start drinking water, remove tight-fitting clothing and take a cool shower or bath. If you have any concerns or if your condition doesn’t improve after a few minutes, call 911 immediately.

Other heat related illnesses include:

Heat rash -occurs when the sweat ducts to the skin become blocked or swell, causing discomfort and itching.

Heat cramps- which occur in muscles after exercise because sweating causes the body to lose water, salt, and minerals aka -electrolytes.

Heat edema – swelling in the legs and hands, which can occur when you sit or stand for a long time in a hot environment.

Heat tetany - (hyperventilation and heat stress), is usually caused by short periods of stress in a hot environment.

Heat syncope - or fainting, which occurs from low blood pressure when heat causes the blood vessels to expand and body fluids move into the legs because of gravity.

[SPECIAL SECTION: Weather blog]

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