From the Research
Antipsychotic medications can cause hyponatremia (low sodium levels in the blood), primarily through the mechanism of syndrome of inappropriate antidiuretic hormone secretion (SIADH), as supported by the most recent study 1. The cause of hyponatremia induced by antipsychotic medication is multifactorial, but the primary mechanism is thought to be SIADH, which is characterized by excessive secretion of antidiuretic hormone (ADH) leading to water retention and subsequent dilutional hyponatremia. Some key points to consider in the management of antipsychotic-induced hyponatremia include:
- Identifying the causative medication and potentially switching to an alternative antipsychotic with lower risk, such as aripiprazole or brexpiprazole, which have lower reported associations with hyponatremia 1.
- Monitoring sodium levels, especially during the first few weeks of therapy or after dose adjustments, and establishing baseline sodium levels before starting treatment 1.
- Risk factors for antipsychotic-induced hyponatremia include older age, female gender, concomitant use of diuretics or SSRIs, and pre-existing conditions like heart failure or renal impairment 1, 2.
- Management of hyponatremia involves fluid restriction, discontinuation of the offending medication, and potentially replacing it with an alternative antipsychotic, with sodium correction being gradual to prevent osmotic demyelination syndrome 1, 3. It is essential to note that the incidence of hyponatremia may be higher than currently thought, and both newer atypical antipsychotics and older drugs have been associated with the development of hyponatremia 4, 5. Therefore, healthcare professionals should be aware of the potential for severe hyponatremia with the use of commonly prescribed antipsychotics and monitor patients closely, especially during the initial treatment period.