Hiponatremia in the practice of a psychiatrist. Part 1: SIADH syndrome and drug-induced hyponatremia.

Abstract

Abstract Introduction. Hyponatremia is an important part of psychiatric practice. In order to analyze its causes and symptoms, the literature on hyponatremia in psychiatric patients has been reviewed. The work has been divided into two separate manuscripts. In the first one the authors discuss the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and hyponatremia occurring with the use of psychotropic drugs (antidepressants, antipsychotics, normotimics), while the second paper discusses research on psychogenic polydipsia. The causes of hyponatremia in patients treated in psychiatric wards include: water intoxication associated with polydipsia, somatic comorbidities, side effect of internal medicine and psychiatric drugs. The most common mechanism leading in these cases to hyponatremia is the syndrome of inappropriate secretion of vasopressin (SIADH). The SIADH syndrome is a group of symptoms, first described in 1967 by Schwartz and Bartter in The American Journal of Medicine, which results from the hypersecretion of antidiuretic hormone, also called vasopressin, which causes patients to develop normovolemic hyponatremia. The phenomenon of drug-induced hyponatremia in psychiatric practice is generally observed with the use of antidepressants, antipsychotics and anti-epileptic drugs (used in psychiatry as normotimic drugs). Aim and method. The first manuscript includes a review of literature on the syndrome of inappropriate secretion of vasopressin (SIADH) and hyponatremia occurring after the use of psychotropic drugs, and is divided into two subsections: 1. The syndrome of inappropriate secretion of vasopressin (SIADH), 2. Hyponatremia and psychotropic drugs (antidepressants, antipsychotics, normotimics). Conclusion. In the view of the reviewed literature it is extremely important to control the natremia level during pharmacotherapy using the above mentioned drugs, especially in the initial period of therapy.