Background Buprenorphine is a synthetic opioid frequently used in combination with naloxone for the treatment of opioid use disorder (OUD). Overall buprenorphine distribution has increased nationally; however, pronounced regional differences in this distribution have also been identified. The objective of this study was to analyze buprenorphine distribution by three-digit zip codes in Pennsylvania from 2010-2020. Methods Data was extracted from the Drug Enforcement Administrations Automated Reports and Consolidated Orders System (ARCOS) yearly to gather buprenorphine distribution, in grams per 3-digit zip code, from 2010-2020. After compiling this data, a percent change for each 3-digit zip code was calculated to analyze the change in distribution from 2010-2020. The total weight of buprenorphine distributed for the state of Pennsylvania over the last decade was calculated. The amount of buprenorphine distributed in grams per each 3-digit zip code was compared to their population densities to analyze if there was any association between population and buprenorphine distribution. Zip codes that were outside of a 95% confidence interval were considered significant (p < .05). Results Pennsylvania pharmacies and hospitals dispensed 116.3 kg of buprenorphine in 2010. That number increased 217.3% to 369.0 kg in 2020. The 155-zip code (Somerset) experienced the largest increase (885%). In contrast the 190-zip (Philadelphia) experienced the smallest increase (79%). The 155 (Somerset), 169 (Wellsboro), and 177 (Williamsport) zip codes experienced significantly greater elevations relative to the state average. Conclusion Our analysis uncovered that buprenorphine distribution in Pennsylvania from 2010-2020 rose 217%. With the increasing awareness of opioid addiction, and the large number of opioid prescriptions in the US, this increase was expected. The zip codes of 155, 169, 177 showed a statistically significant increase in buprenorphine distribution relative to the overall state average. No zip codes displayed a statistically significant decrease in buprenorphine distribution. Interestingly, some of the more densely populated areas in Pennsylvania were at or below the average state increase of 217% (Pittsburgh 150-152: 228%; Philadelphia 190-191: 79%; Harrisburg 170-171: 202%). Furthermore, the statistically significant zip codes of 155, 169, and 177 were among the least densely populated areas of Pennsylvania. Further pharmacoepidemiological research is needed to continue to characterize, and ideally remediate, the pronounced regional variation in buprenorphine distribution.

BJP was part of an osteoarthritis research team from 2019 to 2021 supported by Pfizer and Eli Lilly. The other authors do not report any conflicts of interest.

This study was supported by the Health Resources Services Administration (D34HP31025).

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This study used ONLY openly available human data that were originally located at: https://www.deadiversion.usdoj.gov/arcos/retail_drug_summary/index.html

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