Characterization of Buprenorphine Utilization for Opioid Use Disorder in the Emergency Department

Individuals with opioid use disorder (OUD) represent a prevalent and increasing population of patients presenting to emergency departments (ED). The ED has emerged as a critical access point for harm reduction strategies and initiation of medication for opioid use disorder (MOUD) and transition to substantiative outpatient care. An institutional guideline was created to assist ED clinicians in the management of buprenorphine (BUP) induction for this population. This study aims to characterize the utilization and prescribing patterns of BUP.

This is a retrospective, single-center, medication use evaluation (MUE) of adults admitted to the ED between January 1st, 2024, through July 31st, 2025, and newly initiated on BUP for the management of opioid withdrawal. Patients were identified through internal databases within the electronic medical record. Opioid withdrawal was defined by the initial Clinical Opiate Withdrawal Scale (COWS) on presentation to the ED. Patients were excluded if they received BUP for other indications or MOUD within the previous 30 days. The primary objective was to characterize BUP prescribing patterns for OUD in the ED. Outcomes of interest included total BUP dose at discharge, adherence to ED BUP treatment pathway, adverse events, ED length of stay (LOS), referrals for follow up treatment, disposition, and rates of ED return visits within 24 hours and at 30 days.

A total of 162 patients were screened and 42 included. The average total daily dose of BUP at discharge was 8 mg, with 20 patients (52%) missing a discharge prescription. The adherence rate to hospital guidelines was 23.8%. Most common reasons for nonadherence include missing COWS documentation at baseline and after BUP doses and follow up referrals. There were no documented adverse events. The average LOS in the ED was 18 hours. Most patients were discharged home (69%), with a small percentage admitted to inpatient (7%) or psych units (12%) or leaving the hospital against medical advice (12%). Return rates at 24 hours and 30 days were 12% and 14%, respectively.

These findings suggest there are significant gaps in ED-initiated BUP despite established guidelines and strong evidence supporting this practice. The absence of adverse events and relatively low return rates support the safety and efficacy of the current practice, although no definite conclusions can be drawn.