Robbie Williams says his drug paranoia once made him want to 'stab himself'.
The 34-year-old British singer has revealed his first teenage experimentation with the drug LSD led him to hallucinate so badly he decided to hurt himself.
Robbie, who was 16 when his first acid 'trip’ went wrong in his hometown of Stoke-on-Trent, said: 'It was at Shelleys nightclub where I had my first acid experience. We were in Goldenhill in someone's kitchen probably.
I was given a tiny piece of paper to ingest. "Afterwards we drove up to the garage and the police were on the forecourt. S**t, I thought. I want to go home, I'm scared. There is only one place I want to be - at home with my mum."
"When I got home American footballs were coming out of the TV. So I decided to go downstairs and stab myself. Mum came out of her room and said, 'What are you doing?'
'I said 'I'm just going downstairs to stab myself - do you want a cup of tea?' "
Robbie endured a well-publicised battle with drugs after leaving boy band Take That in 1995.
He has been admitted to rehab twice, the last time shortly before his 33rd birthday in 2007, when he was admitted to a treatment facility in the US for a dependency on prescription drugs.
Robbie, who recently revealed he wants to be a full-time UFOlogist, has been tipped to become a new judge on UK TV talent show 'The X Factor’.