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.
Calls to Spears' representatives by The Associated Press weren't immediately returned.
Since announcing her separation from Kevin Federline in November, Spears, the mother of two young sons, has been seen partying heavily, and her appearance has been increasingly sloppy.
After her whirlwind weekend, people were talking about her behavior, throwing out theories and weighing in on why her charmed life had taken such a sharp downward turn.
"... This girl is out of control," Joy Behar, a co-host on ABC's "The View," said Monday. "And, she's in a lot of trouble. A lot of people feel this is self-mutilation."
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."
Spears grabbed an electrical shaver at a San Fernando Valley salon and shaved her head bald Friday night. Video on KABC-TV showed a newly shorn Spears with tiny tattoos on the back of her neck as she sat for a new tattoo -- a pair of red-and-pink lips on her wrist.
Esther's Haircutting Studio, where Spears shaved her head, set up a Web site to auction off her hair and other items for a minimum price of $1 million, J.T. Tognozzi, who owns the salon with his wife, 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'd placed the items for sale on the eBay auction Web site, which later took them down, for reasons unknown to him.
