According to celebrity snitches, Britney Spears has a new battle to wage-bulimia.

“She has been making herself throw up while at the rehab center,” an insider dishes.

“She is on medication for bipolar disorder, but the pills are not staying in her system because she is bulimic and is throwing them up before they can help her! Among the questions asked at Promises was ‘Do you feel insecure about your body? Do you often throw up after eating?” said a source familiar with the program. “Britney answered ‘yes’ to both questions, and said she had been throwing up since she was 16.”