Bláthnaid Ni Chofaigh was taken ill last night during the live 'All Ireland Talent Show'.
The presenter was unable to continue and didn't reappear on the live results show on RTÉ 1 at 8.30pm.
Bláthnaid, who is a judge on the show, is believed to be suffering from a recurrence of a twisted bowel condition.
The star underwent three operations for the condition in 2009.
A source told The Irish Daily Star: "She was taken ill after the behind the scenes show on RTÉ 2 and couldn't continue with the results show. She was in a lot of pain - it seems to be her twisted gut problem again."
An RTÉ spokesperson confirmed that Bláthnaid had medical treatment.
