Opioid Prescribing Patterns After Imposition of Setting-Specific Limits on Prescription Duration.

Importance: Despite their widespread adoption across the US, policies imposing one-size-fits-all limits on the duration of prescriptions for opioids have shown modest and mixed implications for prescribing. Objective: To assess whether a prescription duration limit policy tailored to different clinical settings was associated with shorter opioid prescription lengths. Design, Setting, and Participants: This cross-sectional study examined changes in opioid prescribing patterns for opioid-naive Medicaid enrollees aged 12 to 64 years before and after implementation of a statewide prescription duration limit policy in West Virginia in June 2018. Patients with cancer or Medicare coverage were excluded. The policy assigned a 7-day duration limit to opioid prescriptions for adults treated in outpatient hospital- or office-based practices, a 4-day limit for adults treated in emergency departments, and a 3-day limit for pediatric patients younger than 18 years regardless of clinical setting. Data were examined from January 1, 2017, through September 30, 2019, and data were analyzed from June 12 to October 30, 2023. Main Outcomes and Measures: Whether a patient's initial opioid prescription was longer in days than the June 2018 policy limit for a given care setting before and after policy implementation. Interrupted time series models were used to calculate the association between the policy's implementation and outcomes. Results: The analytic sample included 44 703 Medicaid enrollees (27 957 patients [62.5%] before policy implementation and 16 746 patients [37.5%] after policy implementation; mean [SD] age, 33.9 [13.4] years; 27 461 females [61.4%]). Among adults treated in outpatient hospital- or office-based settings, the duration limit policy was associated with a decrease of 8.83 (95% CI, -10.43 to -7.23) percentage points (P < .001), or a 56.8% relative reduction, in the proportion of prescriptions exceeding the 7-day limit. In the emergency department setting, the policy was associated with a decrease of 7.03 (95% CI, -10.38 to -3.68) percentage points (P < .001), a 37.5% relative reduction, in the proportion of prescriptions exceeding the 4-day limit. The proportion of pediatric opioid prescriptions longer than the 3-day limit decreased by 12.80 (95% CI, -17.31 to -8.37) percentage points (P < .001), a 26.5% relative reduction, after the policy's implementation. Conclusions and Relevance: Results of this cross-sectional study suggest that opioid prescription duration limits tailored to different clinical settings are associated with reduced length of prescriptions for opioid-naive patients. Additional research is needed to evaluate whether these limits are associated with reductions in the incidence of opioid use disorder or with unintended consequences, such as shifts to illicit opioids.