Heroin treatment centres will open in several counties outside Dublin as use of the drug continues to grow countrywide. Some experts estimate the true level of addiction to be twice that identified in the last major study in 2002.

"This is by any measure spiralling out of control in many counties and we already know from Dublin what the fallout of that is," said Dr Garrett McGovern, a Dublin-based GP who has specialised in clinical addiction for the past 12 years.

"There are counties with some heroin services and in others there is just nothing.

"Wexford has a large number of drug users and there are no GPs taking patients at all; there is nothing. They have to go to Dublin and get on a waiting list."

Dr McGovern said Kildare was another problem county with no treatment options for drug users but said the true extent of addiction and its treatment requirements is unknown.

The HSE said that last year, of the 69 clinics operating throughout the country, 85% had no waiting lists at all and 3% had a waiting list of around one month. The remaining 12% accounted for the majority of those awaiting treatment.

"To address service dem­ands in this area, the HSE has identified the need for additional facilities around the country and is putting in place a number of additional methadone services in Wexford, Waterford, Kilkenny, Cork, Kerry, Limerick and Louth," said a spokesperson.