Taoiseach Enda Kenny has formally told the Dáil that Alex White has been appointed by Government as minister of state in the Department of Health.
Mr White replaces Roisin Shortall, who resigned last week over what she described as a "lack of support for the reforms in the Programme for Government".
After the announcement, Fianna Fáil leader Micheál Martin said his party was "extremely angry" at the lack of opportunity to put questions to Health Minister James Reilly on the criteria he used to select locations for primary care centres.
Mr Kenny said that Mr Reilly answered a question on this matter last week.
He said that the first private members' debate since the summer break was on a Fianna Fáil motion of no confidence in the minister, a debate which Mr Martin "did not bother to contribute to".
Sinn Féin leader Gerry Adams asked if the newly-appointed minister would have powers over primary care delegated to him.
Enda Kenny said he had already explained that no specific legislation applies to primary care, so the delegation order could not cite it.
Socialist Party TD Joe Higgins said Mr White's previous experience would give him a good training in "how to deal with an entrenched Stalinist regime".