To the Editor.— Hyponatremia and the syndrome of inappropriate antidiuretic secretion (SIADH) have been associated with the administration of a number of medications. We would like to add our case report to that of Luzecky et al,1 who first reported the association of SIADH with the administration of amitriptyline. Report of a Case.— A 51-year-old woman was treated for depression with amitriptyline hydrochloride, 50 mg three times per day. She was otherwise in good health and was receiving no other medications. Six weeks after starting the amitriptyline treatment, she was found in her home in a comatose state. Shortly after admission to the hospital, she had a generalized tonicoclonic seizure. There had been no history of excessive water intake noted by the family. The patient was said to have behaved normally on the morning of her admission. Physical examination was unremarkable, except for conspicuous lethargy. There was no evidence