Report: Britney Spears Taking Diet Pills Before Performances

Is life on the road getting to Britney Spears?

A family insider says Britney was caught by her conservator/dad Jamie Spears popping over-the-counter diet pills and washing them down with Red Bull before a performance on her Circus tour, reports gossip site Betty Confidential.

“Britney was definitely trying to get high by taking too many diet pills and energy drinks,” the source told the site. “Jamie thinks the combination of the two is making her whacked-out and, causing her to lash out in weird angry rampages.”

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But that's not all. The insider said “Britney uses green-tea supplements, [Lab 88’s herbal ephedra-free] Metabo Speed XXX, Dexatrim and apple cider vinegar to control her weight and energy levels. She also pours those 5-Hour energy drinks into her Red Bulls," according to the site.

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Spears, 26, has done several stints in rehab facilities, and is currently not in charge of her own affairs, with a judge granting conservatoriship of her finances to her father, and custody of her two children to her ex-husband Kevin Federline.

Spears has recently been linked romantically to her agent Jason Trawick.