Naloxone prescriptions following emergency department encounters for opioid use disorder, overdose, or withdrawal

Objective: To determine the rate at which commercially-insured patients fill prescriptions for naloxone after an opioid-related ED encounter as well as patient characteristics associated with obtaining naloxone.

Methods: This is a retrospective cohort study of adult patients discharged from the ED following treatment for an opioid-related condition from 2016 to 2018 using a commercial insurance claims database (Optum Clinformatics® Data Mart). The primary outcome was a pharmacy claim for naloxone in the 30 days following the ED encounter. A multivariable logistic regression model examined the association of patient characteristics with filled naloxone prescriptions, and predictive margins were used to report adjusted probabilities with 95% confidence intervals.

Results: 21,700 patients had opioid-related ED encounters during the study period, of which 1743 (8.0%) had encounters for heroin overdose, 8825 (40.7%) for overdose due to other opioids, 5400 (24.9%) for withdrawal, and 5732 (26.4%) for other opioid use disorder conditions. 230 patients (1.1%) filled a prescription for naloxone within 30 days. Patients with heroin overdose (2.6%; 95%CI 1.7 to 3.4), recent prescriptions for opioid analgesics (1.4%; 95%CI 1.1 to 1.7), recent prescriptions for buprenorphine (1.9%; 95%CI 1.0 to 2.9), and naloxone prescriptions in the prior year (3.3%; 95%CI 1.8 to 4.8) were more likely to obtain naloxone. The rate was significantly higher in 2018 [1.9% (95%CI 1.5 to 2.2)] as compared to 0.4% (95%CI 0.3 to 0.6) in 2016.

Conclusions: Few patients use insurance to obtain naloxone by prescription following opioid-related ED encounters. Clinical and policy interventions should expand distribution of this life-saving medication in the ED.