Hayden Panettiere‘s cause of death has been revealed.

The actress, who died last month at the age of 36, died from the toxic effects of fentanyl as well as prescription drugs, including alprazolam, known by its brand name Xanax; methocarbamol, a muscle relaxant; and quetiapine, an antipsychotic used to treat schizophrenia, bipolar disorder and major depressive disorder.

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The manner of death was ruled to be an accident, according to the Greenville County Coroner’s Office, which announced its findings early Tuesday.

An autopsy discovered no signs of trauma.

As previously reported, Panettiere was found unresponsive in a Greenville, South Carolina residence, with first responders and EMS responding to a cardiac arrest. Resuscitation efforts were unsuccessful, and she was pronounced dead.

Panettiere, who began acting as a child, had been open about her struggles with substance abuse, revealing in 2022 that she spent years battling an addiction to opioids and alcohol.

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“My saving grace is that I couldn’t be messy while on set and working,” she told People magazine at the time. “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.”

After welcoming daughter Kaya with ex Wladimir Klitschko, Panettiere struggled with postpartum depression, which she sought treatment for but continued to struggle with drinking and using opioids as her relationship with Klitschko crumbled.

“He didn’t want to be around me,” she said. “I didn’t want to be around me. But with the opiates and alcohol, I was doing anything to make me feel happy for a moment. Then I’d feel worse than I did before. I was in a cycle of self-destruction.”

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More to come.