Dutch poison centers track surge in synthetic drug poisonings

Data on the presence of new psychoactive substances (NPS) mainly originate from drug-checking, law enforcement and wastewater analysis sources, while data on NPS poisonings are scarce. In Europe, the documented incidence rate of NPS poisonings is highest in the Netherlands. We investigated temporal trends in NPS poisonings reported to the Dutch Poisons Information Center (DPIC) between 2012 and 2025 and compared these trends across NPS categories. National observational study based on retrospective extraction of recreational drug poisonings (including NPS) from the DPIC database from 2012 to 2025. The DPIC is not accessible to the general public and reporting by healthcare professionals is voluntary. The DPIC database contains standardized case report forms with anonymous patient data and individually (self-)reported substance exposures (not ICD-coded, not analytically confirmed). All cases concerning human exposures to recreational drugs recorded in the DPIC database were included. Primary outcomes were the annual number and annual incidence rate of NPS poisonings reported to the DPIC, relative to the annual number of all recreational drug poisonings. Secondary outcomes were incidence rates of specific (categories of) NPS over time. Predictor was the year of report. Between 2012 and 2025, healthcare professionals reported 19&#x2009;316 recreational drug poisonings, including 4289 NPS-related poisonings, while seeking advice on patient management. The annual number of NPS poisonings increased from 32 in 2012 to 829 in 2025. Between 2012 and 2025 the annual incidence rate of NPS poisonings increased statistically significantly by 19% per year [incidence rate ratio&#x2009;=&#xa0;1.19; 95% confidence interval (CI) = 1.15-1.23]. A higher incidence rate of NPS poisonings was observed in July and December. Cathinones, phenethylamines and benzodiazepines represented 83% of all NPS poisonings. Benzodiazepines were predominant in 2012 and 2024, phenethylamines from 2013 to 2018 and cathinones from 2019 to 2023 and in 2025. The total number of unique NPS notified to the DPIC increased from 17 in 2012 to 176 in 2025. Poisonings with 3-methylmethcathinone (3-MMC), bromazolam, 4-fluoroamphetamine (4-FA), 4-bromo-2,5-dimethoxyphenethylamine (2C-B) and 4-methylmethcathinone (4-MMC, mephedrone) were reported most frequently (5-22% of 4289 NPS poisonings). Poisonings with arylcyclohexylamines, cannabinoids, opioids, arylalkylamines, tryptamines (indolalkylamines), piperidines and pyrrolidines and other substances were rare (every category <5% of 4289 NPS poisonings). No poisonings with aminoindanes or piperazines were reported from 2012 to 2025. The annual incidence rate of new psychoactive substances poisonings reported to the Dutch Poisons Information Center increased by 19% per year between 2012 and 2025. The predominant categories and specific substances involved changed markedly over time.