Keira Knightley Image Credit: Supplied

Actress Keira Knightley has revealed that she was diagnosed with post-traumatic stress disorder (PTSD) after having a mental breakdown at the age of 22.

On The Hollywood Reporter’s podcast, the Pirates of the Caribbean star, who started working at the age of six, spoke about how her quick rise to stardom and the hectic work life affected her mental health.

“It’s amazing looking back at it from the outside, you’re like, whoa, that was hit after hit after hit. But, from the inside, all you’re hearing is the criticism, really. And, also, I was aware that I didn’t know what I was doing, you know? I didn’t know my trade, I didn’t know my craft,” she said. “I knew that there was something that worked sometimes, but I didn’t know how to capture that.”

Knightley was 20 when she was nominated for a Bafta for Atonement, but says she could “only hear the negative stuff”.

“I did have a mental breakdown at 22, so I did take a year off there and was diagnosed with post-traumatic stress disorder because of all of that stuff,” she added.

Her downfall came shortly after she filmed 2008’s The Duchess and it weighed on her so heavily that she couldn’t face red carpets when 2007’s Atonement was being recognised for awards.

As a result, she went into “deep therapy” to get her through the awards season.

“I actually did hypnotherapy so that I could stand on the red carpet at the Baftas and not have a panic attack,” Knightley said.