Mischa Barton on 'destructive' path

Mischa Barton has been on a "destructive path" of drug use, it has been claimed.

The 'O.C.' star - who was sectioned on Wednesday (15.07.09) after being placed under a 5150 hold, a piece of US legislation which means she poses a danger to herself or others - has allegedly been drinking heavily and experimenting with drugs, much to the concern of her friends.

A source told People magazine: "She has been on a destructive path for a while now. Her drug and alcohol use has gotten to a point where it drove people away. I don't think she knows her limits."

The 23-year-old actress is currently under psychiatric evaluation at Los Angeles' Cedars-Sinai Medical Center, but could be released today (18.07.09) if doctors deem her stable or she demands to leave.

Under a 5150 hold order - which can also be used to detain someone who is gravely disabled or has a mental disorder - a person can only be held for up to 72 hours, however, doctors can request an additional 14-day hold if they believe a patient is not fit to be released.

It is the piece of legislation which was used to hold Britney Spears after she suffered a breakdown in 2008.

In April 2008, Mischa pleaded no contest to drink driving and later went to rehab to prove she "was sober".