Despite the so-called 'explosion' of cocaine use throughout Ireland, heroin addiction remains the biggest problem in the country's dedicated treatment centres.
In fact, cocaine only ranks third, behind heroin and cannabis, for people with an illegal drug dependency.
The annual report of the European Monitoring Centre for Drugs and Drug Addiction, published just five weeks ago, confirms heroin's place at the head of the continent's most addictive drug league.
And figures compiled by the Health Research Board have also put Irish cocaine use in context. Just under 2pc of young adults (15-34-year-olds) in this country used cocaine over the last 12 months -- the European average was almost 2.5pc.
Heroin is still, without question, the drug causing most damage to individuals and communities throughout the country and particularly across the capital where the vast majority of users are living.
But whereas heroin was traditionally confined to Dublin, this is no longer the case. In recent years treatment clinics have been established to deal with heroin use in Galway, Waterford, Athlone, Portlaoise, Carlow, Tullamore, Drogheda and other provincial towns.
There are now reckoned to be somewhere in the region of 15,000 Irish heroin users, 13,000 of them in Dublin.
Despite the surge of cocaine use across the country last year, heroin patients remains the biggest group seeking treatment from the Health Service Executive (HSE) in the mid-west area.
HSE Assistant Regional Co-ordinator Rory Keane is responsible for the operational management and strategic development of drug and alcohol services in the region.
The latest figures available for the first eight months of last year show 37pc of 178 patients being treated by the HSE were former heroin users. Just 5pc sought treatment for cocaine.
"The significant changes have been with heroin. This relates primarily to Limerick city where 70pc of our patients would come from. The remaining 30pc would come evenly from Clare and north Tipperary," Mr Keane commented.
The vast majority of heroin users are aged in their early 20s and the youngest person being treated for drug addiction in the mid-west last year was 16-years-old.
"For heroin users in Tipperary and Clare, they will graduate towards Limerick for it as they are not as exposed as they would be in a rural area," he said.
According to Mr Keane, cocaine users are not presenting themselves for treatment to the HSE.
In the north west, the number of people presenting for treatment for opiate addiction has risen significantly in the last five years.
Figures show there was little or no evidence of heroin in the region in 2002 but the picture has been changing gradually since then.
While alcohol continues to be the dominant drug, accounting for 855 treatment referrals in counties Sligo, Donegal and Leitrim in 2004, other drugs accounted for 135 referrals during the same period.
Of the drug referrals, opiates accounted for 19 referrals or 14pc. In 2005 and 2006 this had risen to 20pc.
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