OBJECTIVES: Medication errors (ME) are defined as any preventable event that may cause or lead to inappropriate medication use or patient harm. ME are garnering national attention as evidenced by the National Action Plan for Adverse Drug Event Prevention to drive prevention strategies for high-risk drug classes. We sought to understand the economic burden of ME that lead to preventable adverse drug events (pADEs) in US hospitals. METHODS: From a broader literature review on injectable ME in Medline and Embase (2003-2014), we identified eleven articles related to the incidence and economic impact of pADEs arising from all ME.  A supplemental PubMed search identified four additional articles dating back to 1995. All cost estimates were converted into 2014 dollars. RESULTS:   Published estimates of ME cost varied based on population, setting of care, methodology and study period. Three studies estimated the annual cost of pADEs for the inpatient setting at the national level.  A 1999 study estimated that annual national costs of pADEs were $4.8 billion, while a 2012 study showed that injectable-related pADEs alone cost $2.8-5.2 billion. For Medicare beneficiaries, pADEs cost $617 million annually. At the individual hospital level, the total annual cost of pADEs ranged from $0.9 to $5.6 million. Costs per individual pADE differed based on severity, and ranged from $3408 to $6931. Key cost drivers included increased length of stay, additional laboratory testing, routine care, surgical, and other ancillary charges. CONCLUSIONS: This literature review highlights the economic burden of ME in the US. Cost estimates varied considerably due to different definitions, study methodologies, and analytic scope. Given the emergence of pADE harm reduction as a national priority, there is a need for updated research aimed at evaluating the economic impact of medication errors using standardized definitions for types of errors, their severity and the ensuing financial impact.