In the Antimicrobial Stewardship Program (ASP), the pharmacist acts as a pillar in promoting the rational use of these agents through pharmacotherapeutic analysis and pharmaceutical interventions (PIs). Their role, beyond the clinical focus, contributes to the optimization of financial resources through dose, route of administration, dosage, dilution adjustments, and therapy monitoring. The objective of this study was to demonstrate that pharmaceutical evaluation transcends patient safety, directly impacting financial resource management.

We conducted a cross-sectional analytical study to evaluate the economic impact of PIs on antimicrobials between January and April 2025. The reduction of therapeutic costs was quantified based on the average value of the antimicrobial, reconstituting agent, diluent, and supply kits, multiplied by the daily frequency and duration of treatment. The savings were estimated by the difference between pre- and post-intervention costs.

During the study period, 907 PIs related to antimicrobials were performed. Of these, 191 (21%) generated total savings of R$ 125,811.57, reducing the estimated cost from R$ 187,053.34 to R$ 61,241.77 — a 67% reduction. Most savings came from antibiotics (R$ 87,787.61; 185 PIs), while antifungals (6 PIs) contributed R$ 38,023.96. PIs with the greatest pharmacoeconomic impact were related to dose (29.3%), frequency (28.8%), pertinence (15.7%), and treatment duration (15.2%). Critical units (ICU and semi-intensive) accounted for 97 interventions (51%), generating R$ 73,883.26 in savings, representing a 39.5% cost reduction. In non-critical units, 94 (49%) PIs resulted in R$ 51,928.31 in savings, a 20% cost reduction. The substances that most contributed to savings were isavuconazole and ceftazidime-avibactam (48% of total savings; R$ 60,554.43), followed by teicoplanin, meropenem, micafungin, and piperacillin+tazobactam (37%; R$ 47,095.28). The remaining 26 substances accounted for 15% (R$ 18,231.86).

This study demonstrates that pharmacotherapeutic interventions within the context of the Antimicrobial Stewardship Program go beyond patient safety, establishing themselves as an essential strategy for optimizing financial resources. Analysis of the period from January to April 2025 revealed that only 21% of the interventions resulted in savings of R$ 125,811.57, leading to a 67% reduction in antimicrobial treatment costs.