Mac Miller’s Cause of Death Revealed Rapper Mac Miller’s September death was the result of an accidental overdose, according to a toxicology report released by the L.A. County Coroners Office. Fentanyl, cocaine and alcohol were found in Miller’s system. The combination of the drugs — an autopsy obtained by Rolling Stone describes the use as “recreational” — caused the rapper’s death.

Fentanyl is a synthetic opioid 30 times more powerful than heroin. It’s one of the deadliest drugs associated with the ongoing opioid crisis, and the leading cause of accidental overdose deaths, surpassing heroin.

In the past few years alone, fentanyl has killed a number of high profile musicians including Prince, Tom Petty and Lil Peep, who all died under similar circumstances to Miller.

Miller struggled with substance abuse throughout his life and had spoken openly about it in the past. His early career was marked by a dependence on lean — a mixture of promethazine and codeine — though he was able to kick the habit for a time.

Miller went through bouts of sobriety, but had started drinking again this year, leading to a DUI arrest this May.

According to the autopsy, a bottle of alcohol, a bottle of prescription pills and a “white, powdery substance” were all found in Miller’s home after his death.

Throughout his career, Miller was frank in his assessment of his own struggles with his addictive tendencies, bringing them up in his music and in interviews.

He brought to his music, and his life, a keen sense of his own mortality. “Only so much time left in this crazy world,” read one of his tattoos, according to the autopsy report.

Miller’s death in September came at the critical apex of his career — his latest album, Swimming, was widely considered to be his best, and an indication that he had far more to offer as an artist.

Last week, a tribute concert was held in his honor, benefitting the newly founded Mac Miller Circles Fund, a charity established in his name.

Travis Scott, Chance The Rapper, SZA and more performed at the show, and many of Miller’s friends and collaborators weighed in with what made him a talented artist.