In 2004 the Food and Drug Administration (FDA) required a black-box warning on antidepressants that describes a possible suicide risk in children. An analysis of the events, evidence, and FDA actions reveals information asymmetries that affect various players' ability to identify and act on risks. Antidepressant use declined sharply overall, not just among children, and the FDA's emphasis on the proven efficacy of fluoxetine (generic Prozac) did not prompt dramatic shifts in prescribing. We conclude that risk communication strategies need to be refined, to ensure intended results.