Britney Spears entered rehab Tuesday after a bizarre weekend that included shaving her head and getting a new tattoo.
Spears' manager, Larry Rudolph, told People magazine's Web site that Spears, 25, had voluntarily checked herself into an undisclosed treatment facility.
"We ask that the media respect her privacy as well as those of her family and friends at this time," Rudolph was quoted as saying.
The Web site TMZ.com said Spears had entered an inpatient facility in Los Angeles after family members pressed her to check in.
Meanwhile, the hair salon where Spears shaved her head said Tuesday it wants to auction off her hair and other items for a minimum price of $1 million (EUR760,000).
Calls to Spears' representatives by The Associated Press were not returned Tuesday.
Since she announced her separation from Kevin Federline in November, Spears, the mother of two young sons, has been seen partying with Paris Hilton, and her appearance has been increasingly sloppy.
On Friday night, Spears grabbed an electrical shaver at a San Fernando Valley salon and shaved her head bald.
"We are witnessing Britney in the midst of a breakdown," Ian Drew, editor at large at Us Weekly magazine, told the AP.
"She is a child star unraveling, and is the perfect example of when a child star evolves into an adult and doesn't have someone telling them what to do, or giving them the right affirmative advice, and the right support," Drew said. "She basically started out very young in a competitive business."
New York-based psychiatrist Gail Saltz said she would not be surprised if Spears, mother to 5-month-old Jayden James and 1-year-old Sean Preston, was suffering from postpartum depression.
Her public split with Federline is not helping matters, Saltz said. She suggested that Spears' seemingly impulsive decision to shave her head was "a blatantly self-destructive, you know, desperate kind of act."
Esther's Haircutting Studio, where Spears shaved her head, set up a Web site to auction off her hair and other items for at least $1 million (EUR760,000), J.T. Tognozzi, who owns the salon, told the AP on Tuesday.
"This is it, the opportunity of a lifetime," according to BuyBritneysHair.com. The winning bidder gets Spears' dark, knotty hair extensions, the clipper she used to cut them off, the Red Bull she drank at the salon and her cigarette lighter.
Tognozzi said he had placed the items for sale on the eBay auction Web site, which later took them down, for reasons unknown to him, reports AP.
Craig Ferguson, host of CBS' "The Late Late Show," said that after seeing photos of Spears' shaved head, he reconsidered making jokes at the expense of the "vulnerable."
"For me, comedy should have a certain amount of joy in it," he told viewers Monday. "It should be about attacking the powerful the politicians, the Trumps, the blowhards going after them. We shouldn't be attacking the vulnerable."
Ferguson, who recalled his battle with alcoholism, said: "Now I'm not saying Britney is alcoholic, I don't know what she is alcoholic or not but she clearly needs help."