Previous self-harm attempts are a known risk factor for subsequent suicide completion in adults but is unestablished among adolescents and young adults. Our objective was to determine the mortality rate for patients 10–24 years of age following discharge from the hospital after a non-lethal, intentional overdose.

A retrospective cohort study was conducted of patients aged 10–24 years seen between 2017 and 2022 by the medical toxicology consultation service (MedTox) at a large tertiary care center who experienced a non-lethal, intentional overdose and survived this encounter. The National Death Index (NDI) was examined to determine whether any of these patients subsequently died. We characterized MedTox consultations by age, sex, and substances used. Among those who died, we descriptively characterized the patient's demographics, exposure, and clinical characteristics.

There were 1295 consultations for 1147 patients. Females accounted for 71 % of encounters, and most consults were for those aged 14–17 years (51 %), followed by those 18–21 years (25 %). Most commonly identified substances included acetaminophen (26 %), diphenhydramine (9 %), and ibuprofen (8 %). We identified 4 (<1 %) deaths identified from the NDI: two patients died by asphyxiation, one died by intentional overdose, and one died due to complications from chronic medical conditions.

Our observed mortality was lower compared to other studies (0.7 % - 13.3 %), which may have been due to protective factors (e.g., multidisciplinary evaluations) built into the institutional protocols at this center. Future studies will attempt to qualitatively and quantitatively identify individual- and system- level mechanisms in the pathway between self-harm and long-term health outcomes.