Dehydration

Vital organs such as kidneys, brain and the heart cannot function without a certain amount of water and salt. When your body loses more fluids (such as urine or sweat) than it takes in, you dehydrate and your body cannot function properly. In the case of a "long lie" you may not be able to get something to drink for a longer time.

If you feel thirsty and have a dry mouth and dry lips your body gives you the first signs of a beginning dehydration. As the condition progresses your eyes may have a sunken look, your skin may lack its normal elasticity, you may experience muscle cramps, rapid breathing and an abnormal pulse. Severe dehydration can cause kidney failure.

Mild dehydration can be treated by drinking frequent, small amounts of fluids. In the case of a severe dehydration the person should be admitted to hospital straight away, where he or she is given fluids intravenously (through a vein).

The easiest way to avoid dehydration is to drink at least 2 litres of water each day. Coffee and tea do not count as 'proper' fluids as they make you pass more urine by their action on special centres in the brain.