Knowledge, Attitudes, and Practices of the Mexican Population Regarding the Disposal of Medications: A Cross-Sectional Study

Background and Objectives: The improper disposal of expired and unused medications (EUM) poses significant environmental and health risks. Discarding EUM in household trash or drains leads to accidental poisoning, illegal trade, and ecosystem contamination. These persistent compounds often resist wastewater treatment, disrupting ecological balance and contributing to antimicrobial resistance, thereby increasing morbidity and mortality rates. This study aims to analyze the knowledge, attitudes and practices (KAP) and related factors of the Mexican population regarding the disposal of EUM. Methods: A cross-sectional, descriptive, and correlational study was conducted via an online survey of adults (18+) from October 2021 to October 2024. Results: Among 6080 participants (95.4% aged 18–59; 65.8% women), a medium level of KAP was observed. Notably, 51.5% did not use specialized disposal containers, only 15.5% knew container locations, and 30.5% correctly identified expiration dates. Significant associations emerged: lower education levels correlated with poorer disposal knowledge, while health-related backgrounds and postgraduate studies linked to positive attitudes and adequate practices. Ordinal logistic regression revealed that being elderly, belonging to a high socioeconomic class, having lower education levels, and lacking health-related studies were significantly associated with poor KAP regarding EUM disposal. Conclusions: Inadequate pharmaceutical disposal in Mexico compromises environmental and public health. Addressing this requires reinforced regulations, professionalized pharmacies, and a comprehensive approach to bridge knowledge gaps. Integrating digital tools—like real-time mapping and QR labeling—with accessible take-back schemes is vital in mitigating hazards and uphold the One Health triad.