According to the Los Angeles County Department of Medical Examiner – Coroner report, Mac Miller died as a result of an accidental overdose involving cocaine, fentanyl and alcohol.
The 26-year-old rapper’s cause of death was confirmed on November 5.
Mac Miller, who rose to fame after topping charts with his debut album in 2011, was found dead at his California home in September.
His ex-girlfriend, singer Ariana Grande, called the rapper “an angel” in a song at the weekend. She was among many stars and fans to pay tribute to the performer following his death.
Ariana Grande and Mac Miller, who met in 2012, collaborated on a number of songs and performed together at the One Love Manchester concert in 2017.
Charges were filed against the rapper in August after he was arrested in May for DUI and hit and run.
Ariana Grande spoke out publicly about ending their “toxic relationship” after fans blamed her for Mac Miller’s arrest.
Chance the Rapper, SZA and Miguel were among the artists to perform at a tribute concert at the weekend.
Fentanyl, a powerful painkiller that tends to be cheaper and more potent than heroin, has played a major part in the opioid crisis.
According to the US Drug Enforcement Administration, an estimated 200 people die of overdoses every day.
Prince had taken the drug before his death in 2016.
Fentanyl was also a factor in the fatal overdose suffered by Lil Peep in November 2017.