The HSE have asked people to stop queuing up at UCD after thousands descended on the walk-in vaccination clinic this morning on the first day that over-50s can receive a booster.
And Croke Park's vaccination centre has also hit its full capacity.
Reports on social media indicated that up to 2,000 people had gathered at the university, with the queue for jabs snaking through the campus.
And the HSE has had to step in and issue a statement asking people to stop getting in the ever-expanding queue.
They also presented the Shoreline Leisure Centre vaccination centre in Greystones, Co Wicklow as an alternative for those who were planning to go to Belfield.
The short statement read: "Please do not go there as the centre is at capacity.
"Shoreline vaccination centre is open from 9 to 5."
And a number of hours later, the HSE simply tweeted: "Croke Park is at full capacity for this morning".
Today is the first day that those aged 50-59 were eligible for Covid-19 booster vaccines.
“We will also have walk-in centres open to people to get their vaccine and as ever we encourage everybody to avail of the vaccine,” the HSE's Anne O'Connor told RTE's Morning Ireland yesterday morning.
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