Hypernatremia, a condition defined by elevated serum sodium levels usually resulting from a deficit in free water. The podcast categorize the disorder into hypovolemic, isovolemic, and hypervolemic types, using urine osmolality and sodium concentration to distinguish between renal and extrarenal causes. Patients often present with neurological symptoms caused by cellular dehydration, such as confusion or seizures, necessitating a careful diagnostic approach to determine the fluid volume status. Clinical management focuses on gradual sodium reduction using hypotonic fluids to prevent dangerous complications like cerebral edema. By calculating the free water deficit and accounting for ongoing losses, healthcare providers can safely restore the body's electrolyte balance through oral or intravenous routes.