Hyponatremia in psychosis

Intermittent hyponatremia occurs in a significant subset of patients with psychotic disorder as a consequence of a marked primary polydipsia and relatively minor and transient impairments in water excretion that appear linked to the underlying mental illness. Hyponatremia does occur in many other psychiatric patients as a consequence of medication-induced impairments in water excretion, which may or may not be aggravated by primary polydipsia. While effective preventative measures have been introduced, hyponatremia is frequently undetected in psychiatric patients, making the recognition and proper management an important, yet neglected, aspect of patient care. Treatment for intermittent hyponatremia includes targeted fluid restriction and clozapine and vasopressin antagonism. For medication-induced hyponatremia, the offending agent should be discontinued and replaced. Hypertonic saline is rarely indicated in either case.