A quarter of all addicts are outside the capital
Almost a quarter of heroin addicts in the State are now based outside of Dublin.
The spread of heroin abuse to provincial towns has meant that no county has escaped the ravages of the deadly drug.
However, there is no danger that it will rise to epidemic proportions anywhere despite indications that the abuse is marginally on the increase outside of the capital.
A detailed survey is being carried out for the first time in six years to pinpoint the number of addicts, using information supplied by gardai, treatment clinics and other agencies.
Early estimates suggest there are about 21,000 heroin addicts in the State, with 16,000 of those based in Dublin.
The overall number is reckoned to have been stable over the past few years with a minor increase in the provinces.
But street demand is still sufficient to attract the attention of major drug traffickers.
Last month detectives from the Garda national drugs unit seized a haul of 27 kilos – the biggest heroin find in the State in the past five years – when they stopped an articulated truck on the M1 motorway at Drogheda.
An initial street value of €4.05m was placed on the shipment but it has since increased substantially because the purity level of the shipment meant it could have been cut three or four times before it was sold to addicts and this would have pushed up its value.
Twenty years ago the heroin market was restricted mainly to the area between the two canals in Dublin with small pockets in areas such as Ballyfermot and the greater Dun Laoghaire area.
But gardai and the health authorities are now tackling heroin problems in provincial cities such as Cork, Limerick and Waterford while in Galway, particularly in the past two years, concerns have also been raised over an increase in abuse, mainly due to the trafficking activities of an eastern European gang there.
Pockets of the Midlands counties have also been plagued by dealers with affected towns including Athlone and Longford while traffickers are also targeting Carlow, Birr, Portlaoise, Tullamore and Drogheda with smaller problems in parts of Cavan, due to an influx of criminals from Dublin.
A spillover of gangsters from Limerick city has resulted in an increase in drug-related crime in parts of Tipperary including Clonmel, Carrick-on- Suir and Tipperary town.
But the overall number of heroin users is regarded by experienced anti-drugs detectives as "quite stable".
That stability is mirrored in Europe but the overall number of seizures has fallen considerably.
According to the latest EU report, issued two months ago, heroin seizures annually between 2002 and 2010 worked out at around 50,000.
But since then, the total has plummeted to an estimated 32,000 while the quantity of heroin seized in 2012, five tonnes, was the lowest reported in the last decade and equivalent to only half of what was recovered in 2002.
However, those using heroin, or a range of synthetic opioids such as methadone and buprenorphine – which help reduce withdrawal symptoms – as their primary drug, represent 46pc of all users entering specialised treatment.
Ireland now ranks third in terms of drug deaths per one million population, with 70 fatalities a year, compared with the European average of 17.
And the latest heroin-related death was recorded in Kilkenny earlier this week.
All these statistics highlight reasons why treatment clinics have spread to all of the big provincial towns and are no longer confined to the major cities.