Authorities have yet to reveal Panettiere’s official cause of death, with toxicology results potentially taking up to 12 weeks to complete.
However, investigators reportedly encountered what may be a significant clue at the scene. Narcan, the emergency medication used to reverse opioid overdoses, was found inside the apartment where the actress died.
The drug was used in a desperate effort to treat Panettiere, as both the starlet and Brian were found unresponsive when his brother, Zach Hickerson, arrived and called 911.
Brian regained consciousness, but the Ice Princess star was already in “cardiac arrest” by the time paramedics arrived at the scene.
In grim radio transmissions, EMTs reported “CPR (was) in progress” for an apparent “overdose,” but despite desperate efforts to revive Panettiere, she was pronounced dead at the scene.
Zach later revealed in August, “I immediately called 911, and Brian gave her Narcan.”