Sometimes, in extremely hot and humid conditions, people sweat so much they become dehydrated. If this happens, sweating may cease, while the body's internal temperature continues to rise. If the heatstroke victim is not cooled down, he or she may become confused and delirious, or loose consciousness. Treatment involves getting the person out of the sun and into a cool spot, covering him or her with damp sheets, or spraying the individual with water. The victim can also be immersed in a tub of cold water, if possible, and immediate medical assistance should be obtained.
Dehydration is the principal cause of fatalities in Death Valley.
The hot dry air just sucks the moisture out of the human body. You can lose over one gallon of water just sitting in the shade on a summer day in Death Valley. By the time you have lost a gallon you begin to feel tired and apathetic. Most of the water lost comes from your blood, and as it thickens, your circulation becomes poor, your heart strains, your muscles fatigue, and your head aches. By the time you have lost two gallons of water your tongue is swollen, you can hardly keep your balance, your muscles spasm, and you are becoming delirious.