"It started with ecstasy. I loved ecstasy. Loved it, loved it. It was great at first, then it just went ..." the Black Eyed Peas front woman, 34, says.
When high, she suffered from spells of paranoia and she blacked out the windows in her apartment, convinced she was under FBI surveillance. She also had delusions and once had an eight-hour conversation with a laundry hamper. Another time, a drug dealer held a gun up to her head as she tried to buy marijuana in a bad neighborhood in L.A.
Of crystal meth, which became her drug of choice, she says, "It ruins you."
Fergie, who will star alongside Penelope Cruz in the musical "Nine" this fall, blames some of her past troubles on being a child star.
"What happens when you're a child professional is that you have to be, well, professional. You're taught not to have tantrums, to always people-please," says Fergie, who appeared in Disney's "Kids Incorporated" from 1984 to 1990.
She admits, "That's part of how I got into [drugs] later."
Fergie says her "publicists get really mad with [her] for talking about" her struggles.
"But I don't care," she adds. "For me, it's something I went through. It's an epidemic, and it's important to talk about it because it's a very, very hard thing to stop."
Fergie admits she's still judged for her past even though she hasn't used drugs in 10 years.
"I'm trying to get a thicker skin. I like to be aware of people's perceptions of me, but when you put it as a priority, as a means to judging your worth, that's when it can be dangerous," she says.
"There's no rule book on how to do this," she continues.
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