Recent guidelines from the Institute for Safe Medication Practices have warned of the risk of blood-borne disease transmission associated with insulin pen sharing in hospitalized patients and provide recommendations for safe practices.  This paper describes the impact on insulin pen sharing after the implementation of safe practice recommendations (e.g., label redesign, patient-specific bar coding on pens) at a quaternary academic medical center. Institutional efforts resulted in a less frequent pen-sharing events and a decrease in latent errors found during medication drawer audits, such as retained pens after discharge and illegible or missing label.