Food is Medicine (FIM) programs to improve the accessibility of fruits and vegetables (FVs) or other healthy foods among patients with low income and diet-related chronic diseases are promising to improve food and nutrition security in the United States (US). However, FIM programs are relatively new and implementation guidance for healthcare settings using an implementation science lens is lacking. We used a narrative review to describe the evidence base on barriers and facilitators to FIM program integration in US healthcare settings following the Exploration, Preparation, Implementation, and Sustainment (EPIS) Framework. Evidence surrounding the EPIS Inner Context was a focus, including constructs Leadership, Organizational Characteristics, Quality and Fidelity Monitoring and Support, Organizational Staffing Processes, and Individual Characteristics. Peer-reviewed and grey literature about barriers and facilitators to FIM programs were of interest, defined as programs that screen and refer eligible patients with diet-related chronic disease experiencing food insecurity to healthy, unprepared foods. Thirty-one sources were included in the narrative review, including 22 peer-reviewed articles, four reports, four toolkits, and one thesis. Twenty-eight sources (90%) described EPIS Inner Context facilitators and 26 sources (84%) described FIM program barriers. The most common barriers and facilitators to FIM programs were regarding Quality and Fidelity Monitoring and Support (e.g., use of electronic medical records for tracking and evaluation, strategies to support implementation) and Organizational Staffing Processes (e.g., clear delineation of staff roles and capacity); although, barriers and facilitators to FIM programs were identified among all EPIS Inner Context constructs. We synthesized barriers and facilitators to create an EPIS-informed implementation checklist for healthcare settings for use among healthcare organizations/providers, partner organizations, and technical assistance personnel. We discuss future directions to align FIM efforts with implementation science terminology and theories, models, and frameworks to improve the implementation evidence base and support FIM researchers and practitioners.