Update 4.40pm:The Temple Bar Company has suggested that the decision is effectively a decriminalisation of drug use in certain areas of Dublin city.
The company, representing businesses and cultural centres in Temple Bar, does not believe a measured approach has been taken.
Martin Harte, CEO of the Temple Bar Company, said: “The Temple Bar Company collect 1,500 used syringes from our streets every year. In light of today’s decision at cabinet, we are bracing ourselves for an increase in the level of syringe disposals and related anti-social behaviour.
“Minister Catherine Byrne has said that one of the main reasons for opening a centre was to tackle the issues associated with public injecting. Evidence abroad, however, finds no such decrease in numbers injecting publicly and outside of centres.”
EarlierThe government has approved a bill that will allow for supervised injection centres.
Drug users will be able to self-administer and will have access to sterile injecting equipment.
Trained staff in the centres will be on hand in case of an overdose, and also to provide advice on rehabilitation.
The junior minister responsible, Catherine Byrne, has said there is no reason to think people would take drugs in higher doses.
“That hasn't happened,” she said. “When you go in you actually have to say what you are taking and the quantity you are taking. Remember, this isn’t a service for new users. This is a service for people who are chronic injectors and are very very ill.”
The bill was passed by cabinet this morning and, while no location for the first centre has been selected, a trial is planned for Dublin city.
Minister Byrne said the centre would be a "safe harbour" for chronic drug users.
"They will provide a controlled place for people to inject, but will be much more than that - a place to rest, have a chat and access the services people need," she said.
"I believe in a health-led and person-centred approach to the drug problem. For me, this is all about people and looking after the most vulnerable and marginalised in our society."
It is estimated that about 400 people inject on the streets of Dublin every month.
Discarded needles and drug paraphernalia and overdoses are a recognised problem as a result of street injecting, particularly in Dublin.
The Department of Health said injection rooms are particularly effective in reaching out to chaotic drug users and marginalised groups, especially those who use drugs on the streets or in other risky and unhygienic conditions.
It said the experience from 90 facilities around the world showed a reduction in fatal overdoses and transmission of blood-borne diseases, less drug-related litter and no increase in drug usage or drug-related crime.
Ms Byrne said: "The human cost of public injecting is clear and keeps adding up - the lack of dignity, the effect it has on people's health, wellbeing and safety. We know that these facilities are not the sole solution to the drugs problem and many other steps are needed, but I am committed to doing everything we can to help those who need it most."
Staff in the injection facility will be on hand to provide advice on treatment and rehabilitation.
Health chiefs have been asked to gather data and consider options before a final decision is made on the project.
Health Minister Simon Harris said: "I know people have concerns about where this first pilot facility will be located, but I want to assure you that no decisions have been made."