The electrolyte imbalance has a big incidence in hospitalized patients and thehyponatremia (HN) is at the first place and has been present approximately in 34%of the incoming patients, and up to 50% regarding neurological patients; as an effectmortality has increased in the long-term hospitalization, in a high number of readmissions,and hence in an increment in hospital costs.Therefore, it is mandatory to treat, however, in some cases it persists, and it isrefractory on handling it, wherewith drives the diagnosis to two pathologies:Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) and the CerebralSalt-Wasting Syndromes (CSWS); pathologies which are considered the principalcauses for hyponatremia (HN) in the neurological patient.Hence, it is essential to know and learn how to diagnose these clinical entities, with thepurpose to decrease associated complications and the systemic literary review has asa purpose offer an approach to those pathologies, in this way the health professionalcan account for a bigger number on tools to identify and treat the hyponatremia (HN)in the neurological patient.