Fewer young people are starting to use opiates, according to a new Department of Health study.
During 2011 to 2014, the prevalence rates of problem opiate use remained stable at just under 19,000 nationwide.
The study shows an aging cohort effect as existing users grow older, while fewer young people take their place.
More than half of opiate users in Ireland are in the 35-64 age bracket, while, at the end of 2016, a total of 9,000 users were in methadone treatment.