The association between naloxone claims and proportion of independent versus chain pharmacies: A longitudinal analysis of naloxone claims in the United States

Background: Expanding access to naloxone through pharmacies is an important policy goal. Our objective was to characterize national county-level naloxone dispensing of chain versus independent pharmacies. Methods: The primary exposure in our longitudinal analysis was the proportion of chain pharmacies in a county, identified through the U.S. Department of Homeland Security 2010 Infrastructure Foundation-Level Data. We defined counties as having “higher proportion” of chain pharmacies if at least 50% of pharmacies were large national chains. The primary outcome was quarter-year (2016Q1-2019Q2) rate of pharmacy naloxone claims per 100,000 persons from Symphony Health at the county level. We compared the naloxone dispensing rate between county types using 2-sample t tests. We estimated the association between county-level chain pharmacy proportion and rate of naloxone claims using a linear model with year-quarter fixed effects. Results: Nearly one-third of counties (n = 946) were higher proportion. Higher proportion counties had a significantly higher rate of naloxone claims across the study period, in 4 of 6 urban-rural classifications, and in counties with and without naloxone access laws (NALs). The linear model confirmed that higher proportion counties had a significantly higher rate of naloxone claims, adjusting for urban-rural designation, income, population characteristics, opioid mortality rate, coprescribing laws, and NALs. Conclusion: In this national study, we found an association between naloxone dispensing rates and the county-level proportion of chain (vs. independent) pharmacies. Incentivizing naloxone dispensing through educational, regulatory, or legal efforts may improve naloxone availability and dispensing rates—particularly in counties with proportionately high numbers of independent pharmacies.