hormonal and metabolic disorders
Overhydration
Introduction
Overhydration is an excess of water in the body. People can develop overhydration if they have a disorder that decreases the body’s ability to excrete water or increases the body's tendency to retain water. Drinking too much water rarely causes overhydration because normal kidneys easily excrete excess water. Often, no symptoms occur, but in severe overhydration, people may become confused or have seizures. Fluid intake is restricted, and diuretics may be given. (See also About Body Water .) Overhydration occurs when the body takes in more water than it loses. Overhydration can occur when people drink much more water than their body needs. People, particularly athletes, who drink excessive water to avoid dehydration can develop overhydration. People may also drink excessive water because of a psychiatric disorder called psychogenic polydipsia. The result is too much water and not enough sodium (an Overview of Electrolytes ). Thus, overhydration generally results in Overhydration is much more common among people whose kidneys do not excrete urine normally—for example, among people with a disorder of the heart, kidneys, or liver, or among premature infants, whose kidneys are immature. Certain drugs, such as some antidepressants, can also cause overhydration in susceptible people. Overhydration may also result from the Syndrome of Inappropriate Secretion of Antidiuretic Hormone (SIADH) . In this syndrome, the pituitary gland secretes too much Drinking too much water without replacing salt can be harmful, occasionally even in healthy people. 