Dublin City Council has refused permission for Merchants Quay Ireland to run the country's first ever injection room.
The homeless and drugs Irish charity service had applied to run the supervised facility from its city centre building.
The proposal put forward said that the centre would have seven booths that could cater for up to 100 users per day.
This was turned down by the council who said that there was a lack of a policing plan.
They added that it would also have a negative impact on the Irish tourist economy.
This proposed room was part of a major national drugs strategy with supporters saying that it would cut down the amount of deaths by overdose and reduce drug litter.
Merchants Quay Ireland CEO Paula Byrne said that the decision by the DCC was "deeply disappointing".
The decision can be appealed to An Bord Pleanála.
