Zac Efron has admitted he was "living for the weekend" before he entered rehab in 2013.
The 26-year-old featured on Running Wild with Bear Grylls which aired in the United States this week. As the men rested for a while during filming they got into a discussion about Zac's tough time last year.
Zac Efron and Bear Grylls
"The challenging part was never the work…it was sort of the in-between work," the former Disney star confessed when asked about his challenges. "The social aspects. Everywhere you go to an extent there is press."
Zac continued telling Bear that he dreaded going to work on his acting projects following two days off-schedule to do whatever he wanted. The High School Musical actor also revealed he felt under immense pressure to be a good role model.
"Pretty soon, you need a social lubricant," he added. "It was getting to the point where I was caring less about the work and caring more about the weekend. I couldn't wait to go out.
"And sort of let loose and have fun. But when Monday and Tuesday were difficult to get through, then I was like 'ugh this is bad'."
Watch Zac Efron and Bear Grylls do a death-defying drop on the show:
Zac revealed he was drinking too much alcohol at one point when he fell in with the wrong crowd. He told Bear that he wishes not to use anything that doesn't come from within to make him feel better about himself in the future.
"You know I just really never again want to have to take anything from the outside into me, to make me feel good about my outside," he said.