The association between naloxone claims and proportion of independent vs. chain pharmacies: A longitudinal analysis of naloxone claims in the US

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 US 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 two-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. 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, co-prescribing laws and naloxone access laws. Conclusion In this national study, we found an association between naloxone dispensing rates and the county-level proportion of chain (versus 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.