, *Senthil kumar. R

Selective serotonin reuptake inhibitors are widely used anti depressants. It can cause acute onset hyponatremia with or without neurological manifestations due to SIADH (Egger et al., 2006). SIADH (Syndrome of inappropriate antidiuretic hormone secretion) is a diagnosis of exclusion characterised by euvolemia, low serum osmolarity, inappropriately high urine osmolarity and high urinary sodium (Jacob and Spinler, 2006). Many studies have shown that all SSRIs have the potential to cause SIADH but very few studies are available on Venlafaxnie causing SIADH (Dianne et al., 2002). Most of the patients are in the older age groups (Kirchner et al., 1998; Ranieri et al., 1997) only few studies have shown hyponatremia occurring in young age group. We report the case of a patient who developed acute-onset drug induced hyponatremia that progressed rapidly to serious neurological dysfunction, following initiation of Venlafaxine as a treatment for depression