Britney Spears used crystal meth and amphetamines, says ex-manager

Mental breakdowns, battles for child custody, unfortunate paparazzi shots and a shaved head – all things Britney Spears would rather forget.

But now, it's all coming to light. Spears' dirty laundry is being aired in a high profile Los Angeles defamation trial which pits the pop star against her ex-manager Sam Lutfi.

Lutfi is suing the pop star for 15 percent of her earnings that she allegedly promised him while he was her manager in mid-2007 for almost a year, People magazine reported.

In his opening statement at the trial, Lutfi's attorney told the jury that Spears abused amphetamines.

"Most of the things that went wrong related to that habit," said Joseph Schleimer, who claimed the singer told Lutfi she shaved her head bald "because she'd heard drug use could be detected by testing hair, and she feared losing custody of her two sons," People reported.

The Washington Post reported Schleimer also claimed Spears also told Lutfi drug sniffing dogs found a substance that the singer said was "probably crystal meth."

“He was terrified of being her manager when she overdosed,” Schleimer told the jury, the Post reported.