Zac Efron acknowledges addiction issues with Bear Grylls

Though Zac Efron has remained tight-lipped about his stint in rehab last year, the Neighbors star recently opened up to Bear Grylls in an episode of NBC's Running Wild with Bear Grylls, acknowledging the challenges of fame and how it led to him needing a "social lubricant" to cope.

"It was just so quick -- it was shocking," Efron, 26, said about becoming a superstar after his breakout role in Disney's High School Musical. "The challenging part was never the work, that was never it. It was sort of the in-between work -- the social aspects outside of it; everywhere you go … and it can be confusing … and pretty soon you need a social lubricant."

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Though before long, the social aspects of fame took center stage in his life.

"Once it became that … it got to the point where I was caring less about the work and waiting more for the weekend where I couldn't wait to go out and let loose and have fun," he admitted. "But when Monday and Tuesday were difficult to get through, I thought, 'This is bad.'"

Efron now says he is currently in a much better place.

"I just really never again want to take anything from the outside in to feel … comfortable in my present skin, and that takes a lot of work," he said. "It's just meditation and stopping and slowing down your brain."

Efron shocked fans when he entered rehab in April 2013 for problems with alcohol and reportedly cocaine.

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"I was drinking a lot, way too much," he told The Hollywood Reporter in April, also acknowledging there were drugs involved. "It's never one specific thing. I mean, you're in your 20s, single, going through life in Hollywood, you know? Everything is thrown at you. I wouldn't take anything back; I needed to learn everything I did. But it was an interesting journey, to say the least."

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