Mischa Barton is opening up about her recent health scare.

The O.C. star was hospitalized earlier this week at Cedars-Sinai in LA, but now that she’s feeling better, she’s speaking out about what landed her in the hospital — she was drugged on Wednesday, Jan. 25 while celebrating her birthday.

“While having drinks, I realized that something was not right as my behavior was becoming erratic and continued to intensify over the next several hours,” Mischa said in a statement obtained by People.

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MORE: See Adam Brody, Ben McKenzie and the Cast of 'The O.C.' Then and Now

She went on to explain that after she was taken hospital, the staff told her that at some point during the night, she had been given GBH — otherwise known as the “date rape drug.”

“After an overnight stay, I am home and doing well,” the 31-year-old continued. “I would like to extend a big thanks of gratitude to the professionals at Cedars-Sinai for their great care and professionalism. This is a lesson to all young women out there, be aware of your surroundings.”

Mischa was originally taken to the hospital because of mental instability. Neighbors were concerned when they saw the actress hanging over the fence in her backyard wearing only a shirt and a tie, rambling about her mother being a witch and her dog Ziggy Stardust, TMZ reported. Local police and fire department responded to the call for a jumper or possible overdose at her West Hollywood home.

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Mischa Barton after her 2007 arrest.

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"She was speaking incoherently but agreed to go to Cedars-Sinai Medical Center by ambulance,” Sgt. Enrique Mandujan from the West Hollywood Sheriff's Department told USA Today.

The actress has had a history of mental health. Her rise to fame at 17 years old on The O.C. also led to alcohol abuse, People reported. She was arrested of a DUI in 2007, and two years later she was placed on psychiatric hold.

Scroll through the gallery below to see the cast of The O.C. then and now.