Deliberate self-poisoning in four European countries: retrospective analysis of poison centre data

Introduction: Declining mental wellbeing and rising suicidality are major public health concerns. Deliberate self-poisoning is a common form of suicidal behaviour in Western societies. This study examined trends, demographics, and substances involved in deliberate self-poisonings across European poison centres and assessed the feasibility of harmonised data collection.Methods: Retrospective poison centre data from 2017–2022 were collected from four European countries: national data from France, the Netherlands, and Switzerland, and from the Freiburg poison centre in Germany. Using a standardised template, cases were categorised by gender, age group, and substance. Deliberate self-poisonings cases were expressed as a proportion of all poisoning cases. Temporal trends were analysed using exponential smoothing state space models.Results Within six years, poison centres reported 1,783,858 cases, and one in ten (177,921 cases) involved deliberate self-poisonings. Rates varied across countries, ranging from 8% in France to 23% in the Netherlands. Cases with deliberate self-poisoning remained stable between 2017 and 2020, with an increase observed from 2021 to 2022. Females accounted for 70% of cases, rising to 84% among children/adolescents of 5–17 years. Rates among children/adolescents of 5–17 years increased significantly after 2020 in all countries, largely due to a strong increase among females. Substances involved varied by country, but alcohol, benzodiazepines, and antidepressants dominated in adults, while paracetamol and ibuprofen dominated among children/adolescents of 5–17 years.Discussion Common trends in deliberate self-poisoning, particularly in different age groups, are highlighted and challenges of cross-national data harmonisation in European poison centres are demonstrated.Conclusion Deliberate self-poisoning represented a substantial proportion of poisoning cases, with a sharp rise after 2020, especially among children/adolescent females using readily available over-the-counter non-prescription medicines. These findings underscore the need for targeted prevention strategies and demonstrate the value of coordinated data collection. Expanding collaboration across additional countries could enhance monitoring, strengthen trend analyses, and inform public health interventions.