Sources close to the 21-year-old claim Brown had been regularly using heroin, cocaine and Xanax in the past few months, as well as drinking excessively. No official toxicology report has been released.
Another source says Brown has been "in and out" of rehab during the last three years since her mother, Whitney Houston, died. On Feb. 11, 2012, Houston was found dead in a hotel bathtub. Though the singer had died from drowning, an autopsy confirmed that she had drugs in her system at the time.
It has now been 22 days since Brown was discovered and hospitalized. She has been on life support ever since and recently underwent a tracheotomy to prevent an infection from her breathing tube.