#Mild to moderate dehydration is likely to cause:
-Dry, sticky mouth
-Sleepiness or tiredness — children are likely to be less active than usual
-Decreased urine output
-Few or no tears when crying
-Dizziness or lightheadedness
#Severe dehydration, a medical emergency, can cause:
-Extreme fussiness or sleepiness in infants and children; irritability and confusion in adults
-Very dry mouth, skin and mucous membranes
-Little or no urination — any urine that is produced will be darker than normal
-Shriveled and dry skin that lacks elasticity and doesn't "bounce back" when pinched into a fold
-Low blood pressure
-No tears when crying
In the most serious cases, delirium or unconsciousness
COMPLICATIONS OF DEHYDRATION :
If you don't drink enough fluids when you're exercising vigorously and perspiring heavily, you may end up with a heat injury, ranging in severity from mild heat cramps to heat exhaustion or potentially life-threatening heatstroke.
>Swelling of the brain (cerebral edema).
Sometimes, when you're getting fluids again after being dehydrated, the body tries to pull too much water back into your cells. This can cause some cells to swell and rupture. The consequences are especially grave when brain cells are affected.
Electrolytes— such as potassium and sodium — help carry electrical signals from cell to cell. If your electrolytes are out of balance, the normal electrical messages can become mixed up, which can lead to involuntary muscle contractions and sometimes to a loss of consciousness.
>Low blood volume shock (hypovolemic shock).
This is one of the most serious, and sometimes life-threatening, complications of dehydration. It occurs when low blood volume causes a drop in blood pressure and a drop in the amount of oxygen in your body.
This potentially life-threatening problem occurs when your kidneys are no longer able to remove excess fluids and waste from your blood.
>Coma and death.
When not treated promptly and appropriately, severe dehydration can be fatal.