This chapter examines recent debates about the adverse effects of antidepressant use in children and adolescents. It examines an important pair of conceptual commitments that frame these debates: that antidepressants are ineffective, and that antidepressants are risky. Using Derrida’s notion of the pharmakon (“drug,” “medicine,” “remedy,” “poison”), the chapter argues against the critical desire for remedies that do no harm. The efforts to find a purely beneficial remedy (or even simply a better, less harmful remedy) usually suppose that a reliable, clear distinction between poison and cure is possible. Using the examples of Peter Fonagy’s comments on psychoanalysis and mind, serotonin syndrome, and a model of social neuroscience, this chapter is interested in how antidepressant politics might change if we recognize that it is not possible to firmly distinguish between the poisonous character of the pharmakon and its ability to heal.