The former leader of the Progressive Democrats, Mr Des O'Malley, was taken by ambulance from the Dail yesterday afternoon suffering from abdominal pain.
According to a spokesman for the party, Mr O'Malley was brought to the hospital as a precautionary measure.
Mr O'Malley felt ill yesterday afternoon, suffering from dizziness and stomach pain, while in his office in the top floor of the new extension to Leinster House.
He was attended to by the chairman of Fianna Fail, Dr Rory O'Hanlon, before being removed by ambulance to St Vincent's Hospital.
READ MORE
A spokesman for the hospital said last night it was policy not to comment on individual patients.