Cheryl Cole has pulled out of work commitments for the coming days on the advice of doctors.
The X Factor judge has been attending auditions for the next series of the ITV1 talent show since last month.
But her busy schedule is thought to have left her worn out.
A spokesman for the singer said: "Following doctors' advice Cheryl Cole will be cancelling all work commitments for the next week."
Cheryl's publicist would not say what was wrong with her and said he would make "no further comment".
The 27-year-old star, who earlier this year split from husband Ashley Cole, has also been busy touring as a solo act for the first time, supporting Black Eyed Peas, in recent months.
The Girls Aloud star is scheduled to play high-profile shows at the V Festival in August.
The Sun reported that the singer collapsed at a photoshoot for her second solo album on Saturday and had been diagnosed with exhaustion and gastroenteritis.
© Press Association