Mac Miller may have made history with his breakout debut Blue Slide Park, which became the first independently distributed album to bow atop the charts since 1995. But despite the success of the project, the Pittsburgh, Pennsylvania rapper couldn’t handle the criticism of the project, making him turn to drugs.

During an interview with Complex.com for its online cover story, the Rostrum Records signee explained that the harsh reviews made him become addicted to promethazine, better known as “lean.”

“I love lean; it’s great,” he said. “I was not happy and I was on lean very heavy. … I was so fucked up all the time it was bad. My friends couldn’t even look at me the same. I was lost.”

Mac, who was on his Macadelic tour that hit many colleges, said that reviews that branded him a “frat rapper” drove him to substance abuse. He said that critics weren’t focusing on his music but instead was blasting him as a person.

“A lot of the reviews were more on me as a person,” he said. “To be honest, that was even worse. You’re 19, you’re so excited to put out your first album, you put it out—and no one has any respect for you or for what you did.”

Drug abuse wasn’t the only problem that plagued Miller. Last year, Lord Finesse filed a $10 million lawsuit against him for copyright infringement, later settling out of court for an undisclosed sum.

Read the full interview over at Complex.com.

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