David left the house due to medical reasons after falling ill, and although the nature of his illness has not been revealed, viewers knew he had been unwell recently as he was shown sleeping in a spare room separate to the house.
Speaking on ITV's This Morning (18 January), Celebrity Big Brother's Bit On The Side host, Rylan, said: "He's not been well in that house, he's been a bit ill, he's been in the spare bedroom a couple of evenings. He's really not been feeling well so he decided to leave the house on medical grounds. I do think it is the right decision for him.
"We just want to point out, he's not terribly ill but he's really not been right, and I don't think the Big Brother house was the right place for him to be. We wish him all the best."
In scenes to air tonight, viewers will see David tell Big Brother that he is "too sick" to continue in the show.
In the Diary Room he explains that he needs bed rest, and is unable to get that in the house.
"I've been so sick, and I'm really sad as I wish I could stay," he says. "It's something I will never forget. I want to thank all the people that have been supporting me, I want to tell all the cast mates that I love them and I love this country for its support. Thank you Big Brother."
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