Rational Use of Over-the-Counter Medicines and Patient Safety: Evidence and Gaps in Pharmaceutical Practice

Abstract

Objective: To critically analyze evidence on the pharmacist’s role in promoting the rational use of over-the-counter medicines (OTC), identifying usage patterns, associated risks, and impacts of professional interventions. Method: Integrative literature review with a descriptive approach, conducted according to PRISMA 2020 guidelines. A total of 26 studies (2016–2025) from PubMed, SciELO, and Google Scholar were included. Explicit eligibility criteria, independent reviewers, and categorical narrative synthesis were applied. Results: A high prevalence of self-medication (up to 78.4%) was observed, mainly involving analgesics and nonsteroidal anti-inflammatory drugs. Scientific production was concentrated between 2020 and 2022, predominantly with secondary study designs. Evidence shows a consistent association between self-medication and adverse events, with pharmacist intervention acting as a protective fator. Discussion: Pharmaceutical practice demonstrated a positive impact on improving self-care quality, although limited by structural weaknesses and training gaps. A discrepancy was identified between OTC availability and population competence for rational use. Conclusions: Pharmacists play a central role in patient safety and rational use of OTC medicines, requiring strengthened public policies, continuous professional training, and expansion of clinical pharmaceutical services.