A South Carolina coroner listed five substances in her cause of death, while Greenville police said their investigation remains active.
GREENVILLE, S.C. — Actor Hayden Panettiere died from the toxic effects of fentanyl and four other substances, and her death was ruled accidental, the Greenville County Coroner’s Office said Tuesday, more than a month after she was found unresponsive at a residence where she was staying.
The Sept. 22 finding established the official cause and manner of death for the 36-year-old “Heroes” and “Nashville” star. The coroner listed fentanyl, 4-ANPP, alprazolam, methocarbamol and quetiapine as contributing to the toxic effects that caused her death. An autopsy found no signs of trauma that contributed to her death. Although the coroner reached its determination, Greenville police said their separate investigation into the circumstances surrounding Panettiere’s death remains active.
Emergency officials were called at about 1:51 p.m. Aug. 16 to a residence on Easley Bridge Road in Greenville after receiving a report of cardiac arrest. First responders and emergency medical personnel found Panettiere unresponsive and began advanced life-support measures. Those efforts were unsuccessful, and she was pronounced dead at 2:32 p.m., according to information released by the coroner’s office. Authorities said Panettiere, who was from California, had been temporarily staying at the residence.
The coroner initially left the cause and manner of death pending while additional testing was completed. The office said in August that the autopsy had found no trauma that contributed to Panettiere’s death. Weeks later, as reports circulated about possible toxicology findings, the coroner’s office said no official determination had yet been released. The Sept. 22 announcement marked the completion of that process and formally classified the death as an accident.
A more detailed coroner’s report obtained by The Associated Press described evidence investigators collected from the apartment. The report said an investigator found blue pressed pills and a straw on a table that later tested positive for fentanyl. A white powdery substance also was found in a sunglasses case inside Panettiere’s suitcase. Authorities have not publicly explained how each substance entered her system or released the concentrations found during toxicology testing.
The substances listed in the official cause of death included alprazolam, an anti-anxiety medication commonly sold under the brand name Xanax, and methocarbamol, a prescription muscle relaxant. Quetiapine is a prescription medication used to treat several mental health conditions. The coroner also listed 4-ANPP, a chemical associated with fentanyl. The official finding attributed Panettiere’s death to the toxic effects of the substances rather than identifying a single drug as the sole cause.
Greenville police said Tuesday that the coroner’s findings represented one part of the broader investigation and that detectives would continue following leads and gathering information. ABC News reported that the U.S. Drug Enforcement Administration has been assisting the investigation. Authorities have not announced any arrests or criminal charges connected to Panettiere’s death. A representative for her family also said after the coroner’s findings were released that the investigation remained ongoing.
Panettiere became a familiar face on television after beginning her acting career as a child. Her early work included appearances on soap operas and a role in the 2000 football drama “Remember the Titans.” She later gained widespread recognition as Claire Bennet on NBC’s “Heroes” and as country singer Juliette Barnes on “Nashville.” Her performance on “Nashville” brought her two Golden Globe nominations. Her film credits also included “Ice Princess,” “Scream 4” and “Scream VI.”
In the years before her death, Panettiere had publicly discussed addiction, treatment and postpartum depression. She addressed those experiences in interviews and in her memoir, “This Is Me: A Reckoning,” released in May. The book also examined her childhood in the entertainment industry, personal relationships and the 2023 death of her younger brother, actor Jansen Panettiere. Her past statements about substance use provide context to her life but do not establish the source or circumstances of the drugs identified in the toxicology findings.
Panettiere was also the mother of a daughter, Kaya, born in 2014 during her relationship with former fiancé Wladimir Klitschko. She had spoken publicly about motherhood and about Kaya living with Klitschko while Panettiere sought treatment. Her family and representatives asked for privacy following her death, while friends and former colleagues remembered her work in television and film.
The coroner’s ruling has answered the official questions about Panettiere’s cause and manner of death, but it has not ended the law enforcement inquiry. As of Sept. 23, Greenville police continued investigating how the fatal drug exposure occurred, and authorities had not announced arrests or charges connected to the case.
Author note: Last updated September 23, 2026.