Mischa Barton. (AP File)

Troubled actress Mischa Barton is "doing well" after she was released from a Los Angeles hospital over the weekend.

The former The O.C. star was allegedly placed on involuntary psychiatric hold on 16 July after suffering a meltdown and calling cops to her Hollywood home.

The extent of Barton's health crisis remains a mystery, with her representative, Craig Schneider, simply confirming she had sought treatment for a "medical issue".

But Schneider has revealed to RadarOnline.com that Barton is now out of hospital and is preparing to return to work when filming on her new TV show The Beautiful Life begins.

The spokesman adds, "That's the intention, (but) it hasn't been in production yet."

Shooting on the program, created by Ashton Kutcher, was initially reported to have been delayed by Barton's hospitalization, but network chiefs at The CW insist the hold-up was the result of unfinished sets.

Barton, 23, is set to play Sonja Stone, a catwalk beauty addicted to pills, on The Beautiful Life, which is tentatively scheduled to start filming on 31 July.