Hayden Panettiere’s cause of death has been confirmed by the coroner’s office of the county where she died, five weeks after the actor passed away at age 36.
The actor died from “toxic effects of fentanyl, 4-ANPP, Alprazolam, Methocarbamol, and Quetiapine,” according to a statement from South Carolina’s Greenville County Coroner’s Office, released Sept. 22.
The manner of death was accidental, the statement added.
Panettiere’s death was first announced on Aug. 16, 2026, by her father, Skip Panettiere. She had been pronounced dead earlier that day after emergency personnel in Greenville responded to a report of an unresponsive female, who was later identified as the “Nashville” star.
At the time, no cause or manner of death was shared, but Panettiere’s publicist, Kasey Kitchen, said an investigation was ongoing.
Local authorities added in a statement at the time that there were no “signs of foul play or suspicious circumstances” uncovered in the preliminary investigation and that “an acquaintance of Ms. Panettiere placed the 911 call.”
Panettiere leaves behind a daughter, Kaya, 11, whom she shared with ex-fiancé Wladimir Klitschko. In 2018, Panettiere gave up custody of Kaya. She called not living with her daughter “the most gut-wrenching experience of my life” in her 2026 memoir, “This Is Me: A Reckoning.”
Panettiere was open about her experiences with addiction and postpartum depression leading up to her death.
She wrote in her memoir that a doctor told her while she was in treatment in 2020 that she’d “be dead within five years” if she didn’t stop drinking. And she recalled taking “happy pills” at age 16 to help her with media interviews.
“They were the gateway drug that ushered me toward the good of pharmaceuticals and the downfall of addiction,” Panettiere wrote.
The actor had said that she hoped that her candidness would be able to help others going through similar challenges. And at a May 2026 appearance to promote her memoir, she shared that she’d been able to do just that.
“Someone said to me, ‘Because you’ve talked about your mental health, you gave me the courage to be honest about mine and get myself help, and you saved my life.’ And I was like, ‘This is worth it, I can hopefully leave the world a better world than I found it,’” Panettiere said.
How Did Hayden Panettiere Die?
Panettiere died from “toxic effects” of several drugs, according to local authorities. These include:
- Fentanyl: a strong synthetic opioid used for pain relief and as an anesthetic
- 4-ANPP: a precursor to fentanyl usually found in illicit forms of the drug
- Alprazolam: an anxiety medication available under the brand name Xanax
- Methocarbamol: a prescription muscle relaxant
- Quetiapine: an antipsychotic medication used to treat schizophrenia, bipolar disorder and major depressive disorder
Hayden Panettiere’s Cause of Death Explained
The “toxic effects” of medications lead to death when “a toxic amount of a drug, or combination of drugs overwhelms the body,” according to the National Harm Reduction Coalition.
In particular, opioids like fentanyl can render a person unable to breathe because the drugs affect the receptors that drive the body to inhale and exhale. Without enough oxygen, the heart and brain will stop functioning, leading to coma and then death.