A case series on drug induced hyponatremia: uncommon adverse effect of commonly used drugs

ABSTRACT

Older patients suffering from depression and psychosis have markedly increased since last decade. So, has the use of antidepressants and antipsychotics. The prevalence of hyponatremia due to these drugs is common in general as well as psychiatric practice. It may also lead to life threatening morbidity and mortality. Loss of renal function, polypharmacy, dementia and other conditions of advanced age can either exacerbate the severity of hyponatremia or mask its onset. In this case series, total four cases were reported of hyponatremia and drugs causing it were escitalopram, quetiapine, tianeptine and oxcarbazepine. Due to polypharmacy, a chance of hyponatremia was more in these patients. Patients received infusion of hypertonic saline with salt added diet to treat hyponatremia. Symptoms of hyponatremia were improved after the treatment. In all four cases, WHO and Naranjo’s causality assessment revealed ‘possible’ causal relationship with the prescribed drug. Prescribers should be aware of such adverse effect due to these drugs.