Stephanie Pratt smoked crystal meth "12 or 13 times a day" as a teenager.
The 'Made In Chelsea' star has opened up about her struggle with the highly-addictive drug to reveal she was so hooked that she even smoked it before going to and during school at just 14 years old.
In an extract from her new book 'Made In Reality', as published in new! magazine, she says: "I was 14 or 15 [when I first smoked crystal meth] ... I was on the extreme level and addiction developed instantly.
"[I smoked] probably four times before school, then at snack ... Probably 12 or 13 times a day."
The 29-year-old beauty - who previously starred alongside her famous brother Spencer Pratt in 'The Hills' - was attending the prestigious Crossroads School for Arts & Sciences in Santa Monica, California at the time.
And she admits she often got behind the wheel while under the influence of meth and cocaine as her parents attempted to ignore her out of control behaviour.
Stephanie explained: "I didn't care about anything. I could live or die, I didn't care. I had nothing to get out of bed for, nothing was exciting."
However, the stunning blonde - who has now moved from Los Angeles to London to star in the E4 reality show - was eventually arrested in 2006 after she was caught trying to steal $4,000 worth of designer clothes while high on drugs.
She recalled: "I woke up handcuffed to a hospital bed. When I landed back in LA, Mum took me back home and I went upstairs to my old bedroom and I felt so much shame."