Do Local Synthetic Opioid Overdose Deaths Affect Provider Prescribing of Buprenorphine?

Buprenorphine prescribing for opioid use disorder remains far below the scale of the overdose crisis. We estimate the causal effect of county-level synthetic opioid overdose mortality shocks on the volume of buprenorphine treatment delivered, exploiting the staggered geographic diffusion of synthetic opioids from 2013 to 2023. Linking IQVIA Longitudinal Prescription Claims to National Vital Statistics System mortality records, we implement a difference-in-differences estimator with propensity score matching under three complementary exposure measures. Treatment volume increases significantly under all three definitions, with no evidence of differential pre-trends; point estimates for buprenorphine prescribing rates range from 5 to 17 percent of pre-treatment means, emerge within one to two quarters, and grow monotonically thereafter. Our design does not separately identify changes in patient demand and provider behavior, but the increase in unique prescribers is consistent with a provider-side response. The response is concentrated among advanced practice providers, Medicaid patients, and counties with pre-existing buprenorphine infrastructure; counties with little baseline prescribing show no response. Local mortality information acts as a determinant of treatment volume, with effects comparable in magnitude to major legislative interventions aimed at expanding treatment, but appear only where prescribing capacity already exists.