“Mrs. A,” 59-year-old woman diagnosed with hypertension, presented to the inpatient unit with recurrent depressive disorder, with a current episode of severe depression without psychotic symptoms. Treatment history revealed that she had received tricyclic antidepressants and selective serotonin reuptake inhibitors and had had breakthrough episodes. Her routine investigations, including thyroid function test, did not reveal any abnormality. She was started on venlafaxine 37.5 mg/day, along with alprazolam 0.5 mg bid, enalapril 5 mg/day, and amlodipine 5 mg/day. She tolerated venlafaxine well, and gradually it was increased to 150 mg/day. With this dose, by 2 weeks, she showed partial improvement in her depressive symptoms. After this, the venlafaxine dose was increased to 187.5 mg/day. Within 24 hours of the increase in dose, she developed catatonic signs in the form of immobility, withdrawal, rigidity, negativism, mutism, and posturing. There was no associated history of fever or any other signs and symptoms suggestive of infection. Repeat routine investigations did not reveal any abnormality except low serum sodium levels (127 mEq/L; previous level, on venlafaxine 150 mg/day: 144 mEq/L). Symptoms of catatonia responded transiently to injected lorazepam 2 mg–4 mg. Hyponatremia was corrected with fluid restriction and normal saline, and, over the next 1 week, her catatonic symptoms improved. As she showed improvement, was found to have features of delirium, which was treated with olanzapine. After about 3 weeks of resolution of hyponatremia, her depressive and anxiety symptoms reemerged, for which she was started on milnacipran and pregabalin, with which she achieved symptom remission in 6 weeks. Repeated evaluation did not reveal show signs of hyponatremia.