Almost three quarters of young people at Oberstown Detention Campus in Co. Dublin have a substance misuse problem.
A new report by the Lusk centre also shows over half are identified has having a mental health need.
The aims to give an insight into the adversity and trauma the teens in its care have faced.
52 percent of young people arriving had either a diagnosis of ADHD or a referral for psychiatric services.
Over half weren't going to school and at least a third had suffered the loss of one or both parents through death or separation.
However young offenders are only prioritised for mental health treatment if they're suffering from psychosis or schizophrenia.
Oberstown says the report lays bare the challenges it faces in helping young people with complex needs.
It hopes that publishing the information will encourage communities will play their part in helping to turn young offenders' lives around.