TV cook Nigella Lawson admitted in court to taking the class A drug cocaine on two occasions - but denied she is a regular user.
Lawson also said she smoked cannabis - a banned class B drug - but insisted she no longer uses it.
The 53-year-old made the admissions at the fraud trial of two former members of staff at Isleworth Crown Court.
It comes after her former husband Charles Saatchi dubbed her "Higella" and claimed she used cocaine heavily for a year. Lawson denied she was a habitual cocaine user, claiming the allegations had been made in a bid to destroy her reputation.
She told the jury during her evidence: "I have been put on trial here where I am called to answer, and glad to answer the allegations, and to the world's press, and it comes after a long summer of bullying and abuse."
The popular TV cook appeared at the trial of sisters Elisabetta and Francesca Grillo, who are accused of spending thousands of pounds of Lawson and Saatchi's money before the celebrity divorced, earlier this year.
Speaking of the alleged offence by the Grillo sisters, Lawson said: "It's very difficult when you find out that someone you have loved and trusted could behave that way."
The case continues.