Abstract: Catatonia has been reported to occur in various brain pathologies and systemic conditions. We present a case of catatonia associated with hyponatremia treated with a course of electroconvulsive therapy. A 48-year-old woman presented with catatonia and, upon investigation, was found to have persistent/recurrent hyponatremia. Upon investigation also, she was found to have adrenal insufficiency. Her symptoms of catatonia did not respond to correction of hyponatremia, a course of lorazepam, after which she was treated with ECT, with which her catatonia improved.