Numeracy is an element of health literacy that refers to the ability to understand numerically related information. When applied to health behaviors, it describes the degree to which individuals have the capacity to access, process, interpret, and act on graphical and probabilistic health information. As a cognitive and functional skill, low numeracy correlates with poor outcomes in the management of chronic diseases; numeracy is therefore an essential component of patients' capacity to adhere to medication regimens. In this manuscript, we describe novel visual interventions to improve medication adherence in difficult, chronically ill populations. We have used personalized graphical representations of plasma medication concentration and dynamic disease state simulation to overcome poor numeracy. These methods incorporate efficient, precise, and clear graphical data; cartographical techniques focused on judicious use of color intensities; and animation that increases engagement and accentuates information transfer.