What is already known about this topic? US benzodiazepine-involved overdose deaths decreased during 2017–2019; however, since 2019, the illicit benzodiazepine supply increased.

What is added by this report? From 2019 to 2020, benzodiazepine overdose visits per 100,000 emergency department visits increased (23.7%), both with (34.4%) and without (21.0%) opioid co-involvement. From April–June 2019 to April–June 2020, prescription and illicit benzodiazepine-involved overdose deaths increased 21.8% and 519.6%, respectively. During January–June 2020, 92.7% of benzodiazepine-involved deaths also involved opioids, and 66.7% involved illicitly manufactured fentanyls.

What are the implications for public health practice? Improving naloxone availability and enhancing treatment access for persons using benzodiazepines and opioids and calling emergency services for overdoses involving benzodiazepines and opioids, coupled with primary prevention of drug use and misuse, could reduce morbidity and mortality.