Antimicrobial stewardship is a collaborative intervention strategy aimed at promoting the selection of optimal antimicrobial regimens to improve and measure the appropriate use of antimicrobials, thereby fostering rational use of these agents, enhancing patient outcomes effectively, and curbing the wide dissemination of antimicrobial resistance. Recently, nurses' pivotal contribution in multidisciplinary antimicrobial stewardship teams is increasingly recognized. However, the contexts and mechanisms able to facilitate nurses' participation in the complex dynamics of antimicrobial stewardship remain unclear.

This review aims to identify and analyze the mechanisms, contextual factors, and outcomes that promote nurses' participation in antimicrobial stewardship interventions.

This study adheres to the methods of realist review based on the Normalization Process Theory. Preliminary programme theories were generated through an extensive literature review and thematic analysis. A systematic search was conducted in PubMed, EMBASE, CINAHL, Web of Science, CNKI, and Wangfang databases. The final Context-Mechanism-Outcome configurations were determined to validate the final programme theory.

A total of 5635 articles were retrieved; ultimately, 35 studies were included for a comprehensive analysis. The review identified five key configurations clarifying the interactions among contextual factors, mechanisms, and outcomes: (1) Contextual factors: multidisciplinary team collaboration and hospital organizational support. (2) Strategies and mechanisms: articulating nurses' contributions and impact (Coherence-Building), promoting awareness and positive perceptions (Cognitive Participation), enhancing nurses' competencies (Collective Action), fostering collaborative and motivating frameworks, and emphasizing continuous quality improvement (Reflexive Monitoring). (3) Outcomes: improvements in patient outcomes (e.g., faster antibiotic initiation, shorter hospital stays, and lower mortality) and staff outcomes (e.g., enhanced knowledge, confidence, and adherence to antimicrobial stewardship practices).

This realist review has developed a theoretical framework to promote nurses' participation in antimicrobial stewardship practices. This framework emphasizes the complex dynamic mechanisms that facilitate or hinder nurses' involvement in antimicrobial stewardship and aims to implement evidence-based strategies to encourage nurses' participation in antimicrobial stewardship practices. This, in turn, is expected to enhance the effectiveness of hospital antimicrobial stewardship initiatives and improve the quality of patient care within the hospital environment.

This realist review highlights that, at both individual and organizational levels, supporting nurses' professional roles and responsibilities through targeted education, expanded prescribing authority, collaborative frameworks, and continuous quality improvement empowers nurses to integrate antimicrobial stewardship into their daily practice. By delineating the relevant mechanisms, contextual factors, and outcomes, the findings inform the design of complex interventions to sustain nurses' engagement in hospital antimicrobial stewardship programs, and advance the evolution of advanced nursing practice.