The 26-year-old rapper was found dead in his California home on September 7 and the Los Angeles County Department of Medical Examiner-Coroner have ruled his passing was due to mixed drug toxicity of fentanyl, cocaine and alcohol.
Though the amount of each substance wasn't necessarily lethal, it was the combination of drugs that proved fatal.
According to TMZ, the coroner's report told how Mac's assistant found him unresponsive on his bed in a "praying position", kneeling forward with his head resting on his knees.
The assistant called 911 and described the 'Self Care' singer as already being "blue".
Examiners found a 1/4 inch abrasion on the bridge of his nose, and he had blood coming out of a nostril.
Close to Mac's body was an empty alcohol bottle on a nightstand, and he had a rolled $20 bill with white powder residue in his right pocket. A bottle of prescription pills was found in the bathroom.
An autopsy was completed on the star's body three days after he died before it was released to his family.
It was previously revealed that Mac had likely been "dead for hours" before his body was discovered.
Police and paramedics had arrived to his San Fernando Valley home around midday but they were said to have quickly realised he had passed away long before they were called to the scene.
The night before Mac was discovered, he had had friends over to the house to hang out, and they left in the early hours of the Friday morning, with police revealing no one has come forward to say they had seen him alive after that night.
It was previously claimed Mac's California home had been "swept clean" so there would be no evidence of drug use.
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