Background
Accurate and up to date data on changes in poisoning incidence among young people are lacking. Recent linkage of UK primary care, hospital and mortality data allows these to be quantified to inform service delivery.

Methods
An open cohort study of 1 736 527 young people aged 10-24 between 1998 and 2014 was conducted using linked data from the Clinical Practice Research Datalink, Hospital Episode Statistics and Office for National Statistics deaths. Incidence rates (IRs) by poisoning intent were calculated by age, sex, deprivation and year.

Results
Total poisoning IRs increased by 25% from 1998/99 to 2013/14 [adjusted incidence rate ratio (aIRR) 1.25, 95% CI: 1.20-1.30]. Patterns differed markedly by intent. Intentional poisoning rates increased by 52% while unintentional rates remained unchanged. Intentional rates increased almost exclusively among females, gradually between 1998/99 and 2013/14 among 16-18 (88% increase) and 19-24 (36% increase) year olds but only increased among 10-15 year olds in the last 2 years (79% increase). A 2-fold increased risk of poisoning for the most compared to least deprived quintile existed (aIRR 2.21, 95% CI: 2.02-2.23) and remained over time.

Conclusions
Commissioning of primary and secondary prevention services needs to address the growing problem of intentional poisonings among young people.