Miller had long discussed his substance-abuse issues and it was a prominent factor in his recent breakup from the pop star, Ariana Grande.
Back in May of this year, the rapper had totalled his Mercedes-Benz G-Wagon and received two DUI charges for the incident. One was for driving under the influence and another for having a blood-alcohol level above 0.8.
Miller was also set to tour next month for "The Swimming Tour" to promote his latest album and had two stops scheduled in Canada. He was set to perform in Toronto on November 25 and Vancouver on December 10.
The rapper discussed his drug use on the 2014 mixtape he released called "Faces." The mixtape also eerily predicted that Miller would die young.
The rapper had just done a recent profile with the publication Vulture, that was released on September 6, just one day before his untimely death.