This article examines the changing role of 'confessional technologies' (Foucault 1990) over the history of the HIV pandemic, beginning when US public health departments first rolled out testing campaigns and continuing in the present day through the expansion of diagnostic practices to support the development and implementation of pharmaceutical technologies for HIV prevention. Across this decades-long history, diagnostic practices have been shaped by ethical principles, legal mandates, and research priorities, which have compelled the individual who is 'at risk' of acquiring HIV to speak about their sexual practices and thus reveal hidden truths about one's self to an intimate Other (Whitacre 2018). Indeed, public health ethics have long focused on confession as a means for disciplining safe sex and managing pleasure (Race 2007) and relied on these techniques to secure resources for survival (Nguyen 2010). I argue that confessions have recently become a productive means by which to generate evidence about the efficacy of pharmaceuticals. Practices of revealing truth have contributed to clinical evidence for pharmaceutical interventions, including the use of antiretrovirals for oral HIV pre-exposure prophylaxis (PrEP). Considering the contemporary use of confessions in enabling the development of drug products and facilitating market growth, I contend that confessing should be understood as a form of labour.