London, June 7 (IANS): Former "Sex and the City" actress Kim Cattrall has opened up about her struggle with the “tsunami” of chronic insomnia that forced her out of a starring role on the London stage.

Cattrall, who had been due to take the title role in the Royal Court theatre’s production of Penelope Skinner’s play "Linda" last year, said she withdrew on the advice of doctors and for the sake of her sanity, The Guardian reported.

She described the insomnia, which meant she had not slept for 48 hours when she returned to the US from Britain, as a “gorilla sitting on my chest”.

“I didn’t understand the debilitating consequence of having no sleep. It becomes a tsunami. I was in a void,” Cattrall told the new issue of Radio Times. 

“I didn’t want to let down the audience, the theatre, playwright or the actors.

“Letting go of all that was the hardest part but I realised the work that I really needed to do was more important than the play -- it was work or my sanity," she added. 

The actor, who was born in Liverpool but moved to Canada as a baby, had been due to star as Linda, a businesswoman who vows revenge after her office affair goes viral, in the play.

She was replaced with two weeks to go by Olivier award winner Noma Dumezweni. 

Cattrall said she did not listen to the “noise” of criticism on social media after she dropped out of the role. 

“I have my own voice on social media, where I can say: ‘If you are interested in what really happened, the whole story is more complex than being disease of the week’, than someone saying, ‘I have this battle’,” she said.