SSRIS AND HYPONATREMIA

Increasing age, certain medications such as diuretics, disease process es such as malignant neoplasm and schizophrenia, and a history of hypo natraemia or polydipsia may predispose patients to the development of hyponatraemia. In addition, certain psychotropic medications, includin g TCAs, MAOIs, carbamazepine, trazodone and neuroleptics, may predispo se to hyponatraemia, yet a causative role for most has not been firmly established and the effect is most likely to be more idiosyncratic. T he SSRIs have been associated with hyponatraemia in a small number of case reports. The mean age and sex of patients in reported cases is ov er 70 years and predominantly female, and patients were often receivin g concomitant diuretic therapy, The frequency of hyponatraemia in elde rly female patients receiving fluoxetine has been estimated to be as h igh as eight per 1000, The risk of developing hyponatraemia appears to be highest during the first few weeks of treatment, Because of the po tential seriousness of hyponatraemia, if an elderly patient receiving an SSRI develops unexplained symptoms during the first few weeks of th erapy, it is necessary to measure the serum sodium level.