Hyponatremia: A Mechanistic Approach to Diagnosis and Management

Hyponatremia is a common clinical condition and remains one of the most challenging electrolyte disorders to manage. Traditional approaches emphasize categorizing patients based on total body volume; however, this assessment is often difficult and does not align with the underlying pathophysiologic mechanisms. This review advocates for a more mechanistic approach, beginning with the recognition of the primary abnormality-excess extracellular water-rather than focusing solely on the symptom-low serum sodium concentration. By highlighting the relevant mechanisms, this perspective aims to facilitate more intuitive diagnostic and therapeutic strategies to improve patient care.