Water and Electrolyte Metabolism in Diabetes Insipidus

SummaryThe data presented indicate that in diabetes insipidus the serum water and electrolyte concentrations are maintained normal by reason of the unlimited water exchange. Water restriction or sodium chloride ingestion tends to produce negative water balance, hemoconcentration, augmented sodium and chloride levels in the serum, and loss of potassium from the body. Such changes tend to decrease in extent with elapse of time in spite of continued water restriction and salt ingestion. Pitressin rapidly restores the water and electrolyte concentrations of the serum and probably of other body fluids to normal and this is accomplished on a much lower level of water exchange.