Antidepressant-induced Hyponatremia in Postmenopausal Females: A Case Series

Hyponatremia is the most common electrolyte imbalance observed in hospitalized as well as outdoor patients. Antidepressants such as selective serotonin receptor inhibitors and tricyclic antidepressants are reported among the most common drugs causing hyponatremia, especially in the elderly and in patients with known risk factors for hyponatremia. However, there have been only a few case reports of hyponatremia associated with antidepressants such as mirtazapine and flupentixol/melitracen. The exact mechanism of hyponatremia with the use of antidepressants is not known; however, syndrome of inappropriate antidiuretic hormone secretion (SIADH) is presumed to be the reason. Here, we report two cases of antidepressant drug-induced hyponatremia in two postmenopausal females with no other risk factor for hyponatremia: one associated with mirtazapine and the other with flupentixol/melitracen.