Background: Non-fatal opioid overdoses that do not result in an emergency medical system (EMS), emergency department or hospital encounter are not tracked. We aimed to understand the proportion of non-fatal overdoses with and without a healthcare encounter.
Methods: We used data from the REpeated-dose Behavioral intervention to reduce Opioid Overdose inTervention (REBOOT) trial among opioid overdose survivors in San Francisco and Boston. Participants reported the number of non-fatal overdoses over the prior 4-months at baseline and follow-up visits over 16 months. We asked details about the three most recent overdoses, including naloxone administration, EMS attendance, transport to an emergency department, or hospitalization.
Results: A total of 268 individuals completed 1163 assessments. Across the assessments, 150 participants reported a total of 504 overdoses. Complete details were collected for 384 of the overdose events. Naloxone was administered at 306 out of 384 (80 %) overdose events. EMS attended the scene in 177 out of 384 (46 %) of events, with naloxone administration occurring in 159 of these events (90 %); 130 of the 384 (34 %) events resulted in transportation to the emergency department, and only 18 (5 %) led to hospital admission.
Conclusions: Among opioid overdose survivors in urban settings, EMS were present at less than half of self-reported overdoses, emergency department visits occurred in about one third, and admission to the hospital occurred in one of twenty overdoses. Most overdoses involved naloxone administration, frequently by lay responders. Estimating non-fatal overdose prevalence should not rely solely on measures of EMS attendance, emergency department or hospital admissions.
Keywords: Naloxone; Non-fatal overdose; Opioid; Substance use.
© 2025 The Authors.