Hayden Panettiere‘s cause of death has been officially confirmed. The cause was revealed after a post-mortem examination and toxicology report. The Heroes and Nashville star died on August 16, 2026, at the age of 36 after she was found unresponsive at an apartment in Greenville, South Carolina.
On Tuesday, September 22, the Greenville County Coroner’s Office released the findings from its investigation. In a statementthe coroner’s office said, “The cause of death has been ruled as toxic effects of fentanyl, 4-ANPP, Alprazolam, Methocarbamol and Quetiapine.”
The toxicology report found 4-ANPP, which is a chemical linked to fentanyl production and can also be found as a byproduct when fentanyl breaks down in the body. Officials also found alprazolam, a prescription medication commonly sold under the brand name Xanax. The drug is often prescribed for anxiety and panic disorders.
Methocarbamol, a prescription muscle relaxant, was also detected. The report also listed quetiapine, a prescription medication used to treat several mental health conditions. Authorities determined that the combined effects of the substances caused Panettiere’s death.
Hayden Panettiere’s death has been ruled an accident
The coroner’s office also confirmed that Panettiere’s death was ruled accidental. The autopsy found no signs of physical trauma, meaning there was no indication that an injury contributed to her death. Police found no evidence of criminal activity or foul play. The Greenville Police Department has also closed its investigation surrounding Panettiere’s death.
A police spokesperson told Variety“The preliminary investigation has not indicated any signs of foul play or suspicious circumstances. An acquaintance of Ms. Panettiere placed the 911 call.”
Emergency responders were initially called after Panettiere was reported to be suffering from what appeared to be cardiac arrest. Attempts to revive her at the scene were unsuccessful.
Panettiere became widely known after playing Claire Bennet on NBC’s Heroes. She later earned two Golden Globe nominations for her role as Juliette Barnes on Nashville. She also appeared as Kirby Reed in the Scream franchise.
Her death at 36 led to tributes from fans and people across Hollywood. The release of the coroner’s findings now brings the official investigation into her death to a close.