Background: Whilst substance dependence is well-documented as a risk factor for suicide, less is understood about individuals who die by suicide following recreational polydrug use. Cocaethylene, a psychoactive metabolite produced by the co-ingestion of alcohol and cocaine, may be a cumulative risk factor for suicidality. This study examines the sociocultural, psychiatric and toxicological complexity of individuals whose deaths by suicide involved both alcohol and cocaine use.

Methods: Data were sourced from the National Programme on Substance Use Mortality (2007–2023), including coronial reports for 147 individuals where both cocaine and alcohol were present at post-mortem. [The database includes coroners’ reports pertaining to psychoactive drug-related deaths from England, Wales and Northern Ireland]. Descriptive analyses examined sociodemographics, psychiatric diagnoses, prescribed medications, substance use, and method of suicide. 

Results: The cohort was predominantly male (72.4%), aged 25–45, and overrepresented in the most deprived socio-economic deciles. Psychiatric morbidity was high: over half had documented mental health conditions, and 32.6% were in receipt of psychotropic medication at the time of death. Nearly one-third of medicated cases showed markers of pharmacological complexity, including treatment-resistant prescriptions and high-risk polypharmacy. Hanging was the most frequent method of suicide (72.1%), consistent with national trends in suicide.

Conclusion: Individuals who die by suicide following the co-use of alcohol and cocaine appear to represent a highly vulnerable and clinically complex group. Cocaethylene may serve as a marker for heightened psychiatric and behavioural risk. These findings underscore the need for integrated, cross-sector care models and routine suicide risk screening in substance use settings. Structural deprivation, psychiatric complexity and impulsivity are prominent factors in this population.