Unnecessary dilution of ready-to-administer (RTA) syringes could increase the risk of patient harm attributed to errors related to incorrect dose, improper labeling, and the potential for microbial contamination. Although published guidelines endorse the use of commercially available RTA syringes, recent surveys indicate that best practices are not always implemented. The purpose of this article is to review the existing literature and to assess the incidence and nature of errors related to the unnecessary dilution of RTA intravenous (IV) push medications in the inpatient clinical setting. The PubMed database was searched to identify studies of errors related to the use of RTA syringes for IV push medications within the last 10 years. An additional search was conducted using other search engines to identify relevant articles in the grey literature. This literature review concludes that unnecessary dilution of IV push medication in RTA syringes is an unsafe practice that occurs routinely. This practice increases the risk of patient harm through errors related to incorrect dose, improper labeling of syringes, and the potential for microbial contamination of the product. Greater awareness of the risks associated with unnecessary dilution of RTA syringes is still needed to eliminate this unsafe IV push medication administration practice and to thereby further improve outcomes.