Heat Exhaustion and Heat Stroke Causes

Heat exhaustion is typically caused when people who are not well adjusted to heat exercise in a hot, humid environment.

• At high temperatures, the body cools itself largely through evaporation of sweat.
  
  
• When it is very humid, this mechanism does not work properly.
  
  
• The body loses a combination of fluids and salts (electrolytes).
  
  
• When this is accompanied by an inadequate replacement of fluids, disturbances in the circulation may result that are similar to a mild form of shock.

Heat stroke may often develop rapidly.

• Medical conditions or medications that impair the body's ability to sweat may predispose people to this problem.
  
  
• Heat stroke happens in the following two ways:
  
  
  • The classic form occurs in people whose cooling mechanisms are impaired.
    
    
  • The exertional form occurs in previously healthy people who are undergoing strenuous activity in a hot environment.
• 
  
• Infants and the elderly are more likely to have this problem, as are those who are taking antihistamines and certain types of medication for high blood pressure or depression.