BACKGROUND AND AIMS: There has been an extensive literature describing the elevated risk of drug-related death following an individual's release from prison; however, few previous studies have reported nationally representative samples or provided granular detail as to which individual drugs were deemed implicated in death. We aimed to determine the (1) case characteristics, (2) circumstances of death and (3) type of implicated drugs among individuals recently released from prison and dying due to drug-related causes, stratified by the length of time an individual had been released prior to death. We additionally aimed to determine any changes in the number of deaths and the percentage of deaths in which individual drugs were implicated over time.

DESIGN: Retrospective cohort study.

SETTING: Coronial records submitted voluntarily to the observational cohort National Programme on Substance Use Mortality (NPSUM) in the United Kingdom (UK), 1997-2025.

CASES: Decedents who were recently released from prison up to one month prior to their death due to a drug-related cause.

MEASUREMENTS: Information was available on decedent sociodemographics, characteristics of death and drugs implicated in death.

FINDINGS: A total of 597 decedents were found to have died due to a drug-related cause following recent release from prison. Where records reported the exact timeframe between prison release and death (n = 309), 140 were reported to have died within two days of release, 81 between two days and one week and 88 between one week and one month. There was a statistically significant average annual percentage decrease of -3.9% [95% confidence interval (CI) = -6.6% to -1.0%, P = 0.006] of deaths following recent prison release within the NPSUM population over the studied timeframe. Overall, decedents were predominantly male (n = 547, 91.6%), of White ethnicity (n = 410, 68.7%) and had a mean age of 34.2 years (standard deviation 8.8; range 16-71). Accidental poisoning was the most common direct cause of death (n = 433, 72.5%), with opioids the most common class of implicated drug, involved in more than 90% of fatalities (n = 545, 91.3%).

CONCLUSIONS: Over the past three decades relative to the overall UK National Programme on Substance Use Mortality cohort of deaths due to drug-related causes, there have been substantial and reducing numbers of drug-related fatalities among individuals recently released from prison. Accidental poisoning was the direct cause of death in almost three quarters of cases from 1997 to 2025, and opioids were consistently implicated in over 90% of fatalities.