Rational use of antimicrobials is essential to control bacterial resistance, especially during pandemics. The Antimicrobial Stewardship Program (ASP) uses pharmaceutical interventions (PI) to optimize treatments and ensure safe use. This study analyzed PI before and during the COVID-19 pandemic in a private hospital in Ceará, highlighting types of interventions, acceptance rates, and factors associated with physician adherence.

Retrospective observational study analyzing ASP data from 2018 to 2021 in a private hospital in Ceará, via a supplementary health operator. The following PI were assessed: reduction of treatment duration, oral sequential therapy, de-escalation, and class switching. Additionally, dose adjustment and exposure optimization were evaluated, practices already performed by the pharmacy team and incorporated into the ASP from 2020 onward. The study was approved by the Ethics Committee of the Institute of Health and Hospital Management (CAAE 20508519.4.0000.5684).

A total of 7,422 PI were performed, with an overall acceptance of 62.75%. Before the pandemic, acceptance was 69.23%, dropping to 57.91% during COVID-19. Reduction of treatment duration, the most frequent PI (93%), had decreased acceptability from 73.49% to 57.92%, possibly due to staff overload, prolonged treatments, and concerns about the new disease. Oral sequential therapy increased acceptance (27.20% to 54.29%), likely due to the need for early discharge. De-escalation had higher adherence during the pandemic (67.39%), reflecting confidence in narrowing antibiotic spectrum based on culture results and clinical improvement. Class switching improved (25% to 55.81%), mainly due to replacing teicoplanin with vancomycin according to protocols. Aggregated interventions such as dose adjustment and exposure optimization maintained adherence above 80%, indicating physician confidence in clinical pharmacy.

ASP pharmaceutical interventions had good physician adherence, despite decreased acceptance during the pandemic. Ongoing persuasive strategies, collaboration between medical staff and management, and strengthening clinical pharmacy are essential to improve the program. This study reinforces the importance of maintaining structured programs for the rational and safe use of antimicrobials, especially during health crises.