The average Irish person starts drinking at the age of 16, two years before they are legally allowed to consume alcohol.
Figures from the Health Research Board show that more than 40,000 people were treated for problem alcohol use between 2008 and 2012.
The total numbers treated increased from 7,940 in 2009 to more than 8,600 in 2011.
New cases decreased slightly in 2012 but the numbers returning for treatment increased, reflecting a growth in the numbers with chronic alcohol use problems.
One in five are using other drugs along with alcohol.