The former Emmerdale actress, 51, was removed from the compound around Sunday lunchtime after falling ill over the weekend. The Daily Star reports she was taken to a local hospital.
A spokesperson for the show confirmed: "Due to ill health Claire has had to leave the house to receive medical attention."
No further details about Claire's condition have been revealed or when (or if) she will return to the house.
Celebrity Big Brother airs nightly on Channel 5.
So far, two celebrities have been evicted: Kelly Brook's fiancé David McIntosh and Will & Grace star Leslie Jordan.
Six celebrities are up for nomination on Wednesday night.
If you want to find out who is nominated, watch the video below:
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