Hayden Panettiere's Death Caused by Fentanyl and Other Toxic Substances — Coroner

The Greenville County Coroner's Office in South Carolina has confirmed that American actress Hayden Panettiere died as a result of the toxic effects of fentanyl combined with other substances.

In a statement released on Tuesday, the coroner's office classified the 36-year-old star's death as accidental.

Panettiere, best known for her performances in the TV series Heroes and Nashville, was found dead at an apartment in Greenville on August 16.

Authorities said emergency responders who arrived at the scene following a 911 call discovered the actress in cardiac arrest. Despite their efforts, she could not be revived.

The actress had long been open about her battles with mental health and substance abuse, including postpartum depression and addiction issues that impacted her career earlier in life. Having started acting before she turned one, Panettiere had recently shared more about her journey in a newly released memoir, in which she also reflected on the loss of her younger brother.

At the time of her death, her career was on an upward trajectory once again, with her most recent film having premiered in January.

News of Panettiere's passing sent shockwaves through Hollywood and beyond. Her former partner, ex-Olympic and world boxing champion Wladimir Klitschko, publicly honored her memory and vowed that their daughter, Kaya, would always know and remember her mother.

According to the coroner's office, Panettiere — a California resident — had only been "temporarily staying" at the Greenville apartment where she died. Officials have not identified who owned or occupied the property.

A Greenville Police Department incident report indicated that Panettiere's boyfriend, Brian Hickerson, along with his brother Zach, placed the 911 call after discovering her unresponsive on the afternoon of August 16.

The report noted that the two brothers were interviewed separately by police at the scene, and that Brian Hickerson provided officers with a bag containing Panettiere's medications.

The Hickerson family reportedly has ties to Greenville, where some relatives still live. Police records list Brian Hickerson as a California resident, while his brother Zach resides in Georgia.

Panettiere's death, arriving just after the launch of her memoir, has reignited conversations around the difficulties faced by child actors raised in the public eye. In the wake of her passing, several other former child stars have come forward to discuss the pressures that come with growing up in the entertainment industry.