Autopsy results report Hayden Panettiere’s death was caused by an overdose of fentanyl, Xanax, and several other drugs.
The coroner’s office said the incident was accidental, with no signs of trauma found that could have contributed to her passing.
Panettiere, who was 36, was discovered unresponsive at a South Carolina residence last month. She had openly discussed her struggles with substance abuse, including her introduction to drugs during her early career.
The investigation also identified methocarbamol, a prescription muscle‑relaxant, and quetiapine, an antipsychotic medication, in her system.
Fentanyl, a synthetic opioid, has been responsible for hundreds of thousands of deaths in the United States over the past five years.
Emergency responders attempted advanced cardiac life support, but resuscitation was unsuccessful. The Drug Enforcement Agency joined the local police investigation.
Reports indicate Panettiere’s ex‑boyfriend, Brian Hickerson, and his brother were present when emergency services arrived. They had admitted to abusing her substance use.
The actress published a memoir a few months before her death, detailing her addiction battles and postpartum depression. She began experimenting with drugs at 16 during a red‑carpet event for the show "Heroes," receiving a so‑called "happy pill" for energy.
In her book, she noted how drugs and alcohol became something she could not live without. Her brother, Jansen, died at 28 from a heart condition linked to substance abuse.
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