Mischa Barton has been hospitalized, per the recommendation of her doctor, her rep tells ET.

"Mischa lately has looked a little bit more disheveled," David Caplan, senior editor, People magazine says. "Her face is puffy -- that was attributed by some people to having her wisdom teeth out. But her looks really have changed lately compared to how she used to look."

Caplan adds that she is being evaluated by mental health professionals. Allegedly, she is being held under California's involuntary psychiatric hold law, after being taken away by police.

"Right now Mischa is under the involuntary hold, also known as a section 5150 of the California Welfare and Institutions code, allowing authorities to hold a person for up to 72 hours if they present a danger to themselves or to others," Caplan continues.

According to the issue of People on newsstands, Mischa missed the New York premiere of her movie, 'Homecoming.' And this isn't the first time that the former "The O.C." star's problems have been made public.

"In 2007, Mischa was arrested for DUI, marijuana possession -- the charges were later dropped -- and driving without a license in LA. She later checked into rehab," Caplan says.

Mischa was scheduled to return to TV to star in The CW's upcoming fall series, "The Beautiful Life," but her participation is said to be contingent on her recovery.