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.

Identification of risk factors associated with hyponatremia in psychiatric patients: a case-control study

“…Three of the four hyponatremia cases in the case series were over 50 years old, indicated a link between age and hyponatremia. These findings are consistent with recent research, which show that age is one of the most important predictors of hyponatremia, which could be attributable to a variety of factors [ 4 ]. However, another study showed that age also seems to be strongly confounded by drugs and comorbidities which usually are present in the older age and might be responsible for the hyponatremia [ 11 ].…”

“…The study population comprised of a higher population of males (65.7%) which was similar to a study conducted by Joshi HM et al where hyponatremia was significantly more common in male psychiatric inpatients (p<0.04) [4]. There was a statistically significant difference in the mean age of patients in cases and controls.…”

“…Hyponatremia is a prevalent and potentially dangerous condition in psychiatric patients and accounts for 15% of the cases. Among psychiatric patients, hyponatremia is believed to be frequently underdiagnosed because clinical signs may mimic psychopathological symptoms of the underlying condition [ 4 ]. With the progressive loss of kidney function, derangements in electrolytes and acid-base inevitably occur and contribute to poor patient outcomes [ 8 ].…”

“…Moreover, serotonin resets the osmostat and thereby lowers the threshold for ADH secretion [ 18 ]. In a case series, one of the case received combination of trifluoperazine, haloperidol drugs along with quetiapine which was found to aggravate hyponatremia [ 4 ]. A case report by Reddy Mukku et al, found that elderly age, polydipsia, psychiatric illness, antihypertensive medicine (hydrochlorothiazide), and quetiapine are all factors that contribute to hyponatremia which was similar to our study findings [ 12 ].…”

“…Many elderly people are especially vulnerable to hyponatremia as they will be on diuretics. Loss of kidney function, polypharmacy, dementia, and other advanced-age disorders can increase the severity of hyponatremia [ 4 ]. Also, the conditions that increase water intake, such as delusional states, obsessive-compulsive behavior, and dry mouth associated with the anticholinergic side effects of many psychiatric medicines, are potential risk factors for the development of hyponatremia in psychiatric patients.…”