President Michael D Higgins spent the night in hospital undergoing tests after feeling unwell yesterday evening.
The 82 year-old was taken by ambulance to hospital as a precaution after being assessed by a doctor at Áras an Uachtaráin.
A statement says the President was in excellent spirits and has thanked the medical staff for the care he has received.
"Áras an Uachtaráin can confirm that, having felt unwell, President Michael D. Higgins was this evening brought to hospital for precautionary tests.
The President was initially assessed at Áras an Uachtaráin where no immediate concerns were identified but a decision was made to proceed to hospital in order to undergo tests, the initial results of which have been positive.
The President, who will remain in hospital overnight, is in excellent spirits and has thanked the medical staff for the care he has received."