Shifting outpatient medicines dispensing from hospital-based to community pharmacies in Spain: Carbon footprint mitigation in patient mobility

Introduction Patient travel accounts for approximately 5% of the healthcare carbon footprint. This study compared the transportation-related carbon footprint of a conventional hospital-based outpatient medication dispensing model with a hybrid model that integrated community pharmacies as proximity collection points. Methods This retrospective cohort study analyzed travel data from 6158 patients receiving outpatient hospital medications from Hospital del Mar (Barcelona, Spain) in April 2023. Under the conventional model, all patients traveled to the hospital pharmacy. Under the hybrid model, 58.4% of patients remained at the hospital pharmacy model, whereas 41.6% were reassigned to community pharmacies. The carbon footprint (t CO 2 e/year) was estimated using life cycle assessment with territory-specific emission factors across three mobility scenarios. Results The conventional model generated 96.93 t CO 2 e/year (median per patient, 5.05 kg CO 2 e/year [IQR, 2.63-8.48]), with 63.75% of total emissions attributable to just 10% of patients. The hybrid model reduced total emissions to 52.02 t CO 2 e/year (46.33% reduction), including 3.61 t CO 2 e/year from upstream logistics. Patients reassigned to community pharmacies demonstrated a 97.20% reduction in their carbon footprint compared with baseline ( P < .001). These results were consistent across all mobility scenarios, with overall reductions ranging from 44% to 47%. Sensitivity analyses estimated a 96.54% system-wide reduction under full reassignment to community pharmacies and a 29.93% reduction under electric vehicle home delivery. Conclusions Decentralizing outpatient medication dispensing to community pharmacies dramatically reduces the environmental impact of patient travel, representing a highly effective strategy to contribute to the decarbonization of healthcare delivery.