Multicenter toxicological analysis of psychoactive substances in suicide victims in Brazil

To assess the prevalence and toxicological profile of psychoactive substance use among coroner-certified suicide cases in Brazil. We conducted a multicenter cross-sectional study using probabilistic post-mortem blood sampling of suicide victims autopsied at the Institutes of Forensic Medicine between March 2022 and June 2024. Data were collected from forensic units covering metropolitan areas of the state capitals of Pará, Pernambuco, Espírito Santo, and Paraná. Alcohol and other psychoactive substances were analyzed using headspace-gas chromatography and liquid chromatography-tandem mass spectrometry. Among 330 suicide victims, 54.4% tested positive for at least one psychoactive substance. Alcohol was the most detected substance (29.4%), followed by cocaine (21.2%) and benzodiazepines (20.3%). Polysubstance use occurred in 14.5% of cases, most involving simultaneous use of alcohol and cocaine. Substance-positive victims were younger than those without detectable substances (median age: 38 vs. 44 years, p = 0.04). Cocaine use was associated with concurrent alcohol use (OR: 4.05; 95% CI: 2.33-7.03) and death by asphyxia (OR: 2.65; 95% CI: 1.25-5.60). This multicenter toxicological study, the first in Brazil, shows that psychoactive substances are prevalent among suicide victims, with alcohol, cocaine, and benzodiazepines most often detected. The co-use of alcohol and cocaine, especially among younger victims, underscores a risk profile that may intensify lethality. Broader surveillance and longitudinal designs are needed to clarify causal links and strengthen suicide prevention strategies that integrate toxicological evidence with mental health and substance use care.