Minister for Health Stephen Donnelly has failed to be re-elected in Wicklow - losing a seat he has held since 2011.
The outgoing Fianna Fáil TD lost out to Fine Gael's Edward Timmons on the final count in the Garden County.
Mr Donnelly was first elected in the constituency as an Independent candidate on his first election attempt 13 years ago.
He helped co-founded the Social Democrats in July 2015 alongside Róisín Shortall and Catherine Murphy.
During the 2016 election campaign he enjoyed a high profile, representing the Social Democrats in live TV debates.
This would lead to him topping the poll in Wicklow that year with 14,348 first preferences - representing a 20.85% vote share.
Shortly after the election, he left the Social Democrats after a series of disagreements with his co-leaders Róisín Shortall and Catherine Murphy.

One of the significant issues between Mr Donnelly and Ms Shortall and Ms Murphy was that he favoured entering into discussions about joining the Fine Gael-led coalition government, but this was ruled out his co-leaders.
In February 2017, he joined Fianna Fáil.
Mr Donnelly won the last seat in the Wicklow constituency in the 2020 general election when it was still a five-seater.
Following a redrawing of boundaries ahead of General Election 2024, Wicklow was reduced a four-seater after the creation of the Wicklow-Wexford constituency.
Mr Donnelly defended his decision to join Micheál Martin's party, arguing that he could remain "on the margins" or stand up at a time of "national crisis".
Within Fianna Fáil, Mr Donnelly held responsibility as a spokeperson for Brexit until a March 2018 frontbench reshuffle, when he took over as the party's spokesperson on health.
He was elected on the 15th count, along with Simon Harris, in the 2020 general election with 11,018 first preference votes (7.7% vote share).

Mr Donnelly was appointed Minister for Health by then-taoiseach Micheál Martin and remained in the role after Leo Varadkar took over as taoiseach in 2022.
He served in this position during the Covid-19 pandemic and was consequently closely linked to decisions
regarding Ireland’s responses to it, including lockdowns and the rollout of the vaccine programme.
He later defended the decision to allow pubs and restaurants to open during the Christmas period,
despite warnings from the National Public Health Emergency Team.
Mr Donnelly also faced criticism over the CervicalCheck tribunal, with one campaigner - Vicky Phelan - noting she and others affected felt 'betrayed’ after their requests to postpone the tribunal’s establishment were ignored.
More recently, Mr Donnelly was involved in testy exchanges with construction company BAM over the National Children's Hospital.
In a letter to Taoiseach Simon Harris, Mr Donnelly said it was the view of the National Paediatric Hospital Development Board, which is responsible for the hospital project, that "BAM's approach is based on extracting as much money from the Irish taxpayer as possible".
BAM responded saying it particularly rejected Mr Donnelly's claim that BAM was "holding the State to ransom".