Hayden Panettierehas been candid about herstruggles with substance abuseas she transitioned from a child actress into an adult in Hollywood. Now the star is tracing the roots of her addiction, in part, to a pivotal moment when she was just 16 years old.

In an exclusive clip from this week’sRed Table Talkon Facebook Watch, the 33-year-old actress looks back on an instance when people she trusted with her career and her health first set her down an inevitably dark path.

“It was, ‘Here, take one of these, it’s a happy pill, it’ll give you energy,’ so I didn’t think of it at the time as a bad thing or a drug,” she says.

Panettiere now believes the “happy pill” was something “similar to an Adderall,” a prescription stimulant, but said the team member involved acquired the drug from Mexico.

“I should have thought, ‘That’s so sketchy,’ but I didn’t because I trusted the person,” Panettiere admits. “It did give me that little bit of energy and I didn’t feel like, high and out of control, but I did feel happy and like I was looking forward to doing interviews, yes.”

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Hayden Panettiere

Panettiere also notes she didn’t have any inkling the interaction was wrong until she asked for more pills “for personal use” and another of her associates intervened.

“They were to make me peppy during interviews,” Panettiere told PEOPLE in July of the same pills offered to her. “I had no idea that this was not an appropriate thing, or what door that would open for me when it came to my addiction.”

RELATED VIDEO: Hayden Panettiere Reveals Addiction to Opioids and Alcohol: “I Was in a Cycle of Self-Destruction”

Speaking to PEOPLE in July, Panettiere admitted to drinking alcohol and occasionally taking opioids through the early parts of her career — though she said her “saving grace [was] that I couldn’t be messy while on set and working.”

She continued, “But things kept getting out of control [off set]. And as I got older, the drugs and alcohol became something I almost couldn’t live without.”

Red Table Talk @Angela Andaloro

Hayden Panettiere bravely opens up about years of alcohol abuse, crippling postpartum depression, and, for the first time, reveals her truth about giving up custody of her only child. Special guest host and first time mom-to-be Kelly Osbourne joins the Table with a life-changing update about her addiction recovery and pregnancy journey.

Also on Wednesday’s episode ofRed Table Talk, Panettiere discussessigning over full custody of her only child—7-year-old daughter Kaya— to exWladimir Klitschko, calling it the “most heartbreaking thing I’ve ever had to do in my life.”

“Because of the way that it was done, it was very upsetting,” she says. “I mean, it was the worst signing those papers.”

She continues, “I was gonna go work on myself, I was gonna get better, and when I got better then things would change and she could come to me and I could have my time with her. But that didn’t happen.”

Hayden Panettiere bravely opens up about years of alcohol abuse, crippling postpartum depression, and, for the first time, reveals her truth about giving up custody of her only child. Special guest host and first time mom-to-be Kelly Osbourne joins the Table with a life-changing update about her addiction recovery and pregnancy journey.

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The Facebook Watch original seriesRed Table Talkairs new episodes every Wednesday at 12 p.m. ET/9 a.m. PT.

source: people.com