Venlafaxine-induced reset osmostat syndrome: case of a 79-year-old depressed woman.

The presence of hyponatremia, especially in a frail and very old patient, is associated with a greater morbidity and mortality rate. We report the case of a depressed 79-year-old woman who was treated with venlafaxine, in whom a drug-induced hyponatremia occurred in the absence of other possible causes. The case is discussed in the context of the multipotential factors that induce hyponatremia, with particular attention to the geriatric patient.