Ireland has one of the worst levels of drug-related deaths in Europe, it has emerged.
A United Nations (UN) report on the global drug market showed Ukraine, Iceland and Ireland have the highest mortality rates in Europe, with over 100 drug-related deaths per million inhabitants aged between 15 and 64.
Heroin is predominantly ranked as the primary cause of death followed by cocaine, at much lower levels.
There are an estimated 20,000 heroin addicts in Ireland, with almost two-thirds in the greater Dublin area.
Tony Geoghegan, of Merchants Quay Ireland, said he was not shocked that Ireland had the sixth highest rate of heroin use in 2009 - half the levels seen in Scotland and Estonia.
The World Drug Report also revealed heroin use rose in Ireland and Sweden last year while the problem stabilised in most other European countries.
"We were naive to think Ireland was different than the rest of Europe," said Mr Geoghegan.
"I work in the system and we have been aware for a long time that Ireland has a very high level of drug use and related deaths."
"It is underpinned by the lack of access to treatment."
The most prevalent drug in Europe is cannabis, followed by cocaine and amphetamines, the data showed.
The UN study revealed the highest levels of non-medical use of prescription opioids so far have been reported from Northern Ireland.
It said while two-thirds of Europe's cocaine users live in the United Kingdom, Spain and Italy, use of the class A drug was also high in Denmark and Ireland.
The price of cocaine dropped to 68 euro a gram in 2009, compared to 43 euro in the UK, while heroin was 147 euro a gram, or 49 euro in the UK.
Drug seizures have also declined since a peak in 2007.
Mr Geoghegan said the drop in cocaine prices and seizures are a direct result of the recession.
"Heroin is a specialised market while cocaine has wider appeal," he added.
"There are people who are addicted to drugs and people who are not addicted, but take them recreationally. They may have decided to cut back on cocaine for financial reasons.
"But for someone on heron, whether there's a recession or not a recession, it's not going to affect them."
© Press Association