Most know Darryl “DMC” McDaniels for his sick rhymes, hip-hop legacy in groundbreaking group Run-DMC and placement in the Rock and Roll Hall of Fame – but his rock star life was riddled with demons.

Growing Pains: A Tough Transition to Stardom
Growing up in a middle-class family in Queens, New York, McDaniels – a comic book nerd who took up deejaying on his brother’s turntable as a preteen – started rapping for fun with friend Joseph “Run” Simmons as a kid. A shy guy, McDaniels started drinking young, turning to malt liquor (Olde English 800 was a go-to) for a confidence booster. By 15, he was dependent on booze to get onstage to perform.

After high school, McDaniels started college at New York’s St. John University. But when he, Simmons and Jason “Jazz Master Jay” Mizell started performing as Run-DMC, their tracks (first “It’s Like That,” then “Sucker M.C.’s”) took off in 1983 – and so did McDaniels’ alcoholism.

“I started from drinking a 40[-ounce bottle Olde English 800] throughout the day, right before I would go on stage,” McDaniels, now 52 – who discusses his struggles in his new memoir, Ten Ways Not to Commit Suicide, out July 5 – tells PEOPLE.

“But I had more money, so I didn’t have to go buy bottles of beer: I could just buy a case. So that’s when it got obsessive. It got to the point where it was five 40s before I went onstage, but it still didn’t take effect.”

As Run-DMC’s fame grew, so did McDaniels’ struggles. Though he’d written much of the trio’s early tracks, he says Simmons and Mizell didn’t respect his creative input shortly after they broke out.

“When I look back, it all started when I was looking for my confidence,” he says. “I didn’t need alcohol when I was 12 years old, sitting in my bedroom writing just rhymes in my notebooks: it was fun; there was no pressure of, ‘Man, I gotta write this rhyme. I hope it’ll sell.’ When you have expectations, that destroys.”

McDaniels said pressure from his band-mates, label and himself pushed him to drink more and more, and by 1991, he was drinking a case of Olde English 40s a day. Until he ended up in the hospital with acute pancreatitis.

“I was in the hospital for like a month and a half, with everything entered [through the] vein because I couldn’t take anything orally,” he says of his stay, where doctors told him: “‘Miraculously, you don’t have cirrhosis of the liver, but your pancreas is bruised and battered, but it’s still functioning. You’ve got two choices: Drink and die, or not drink and live.'”

After that, McDaniels quit cold turkey. He knew, “if I drink that, I die.”

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