Pedro Gurillo Muñoz

By Mireia Martínez Cortés and Pedro Gurillo Muñoz

Given the widespread use of psychotropic drugs in the population, it’s important to consider hyponatremia as an avoidable and reversible adverse effect and include the detection of high-risk subjects to establish safer medications, as well as early detection measures in routine clinical practice. Although hyponatremia has been especially associated with serotonergic antidepressants (SSRIs), there is also an elevated risk with tricyclics, duals and heterocyclic antidepressants, due to the different mechanisms of action at the renal tubular level and the release of ADH. Hyponatremia secondary to tricyclics with slow CYP2D6 metabolizers have higher plasma concentrations of antidepressants metabolized by CYP2D6. Hyponatremia secondary to SSRIs appears in the first week of treatment, it is “not dose-dependent” and normalization of natremia occurs between 2 and 20 days after stopping the medication. Bupropion, trazodone, mianserin, reboxetine and agomelatine are a safe alternative. Also antiepileptics have been related to hyponatremia. Both typical and atypical antipsychotics have been exposed to an increased risk of hyponatremia, even after adjusted factors such as age, sex and comorbidity. Other factors that favor the onset of hyponatremia act synergistically with psychotropic drugs, such as: advanced age, female sex, concomitant diuretic intake, low body weight and low sodium levels; NSAID, ACEIs, and warm.

Part of the book: Fluid and Electrolyte Disorders