Matthew Perry has revealed that he can't remember much from a three-year period of making Friends, because he was so "out of it."

Perry, 46, who shot to international fame for his role as Chandler Bing in the hit sitcom, has spoken candidly about his past problems with alcohol and prescription drug addiction.

But while the star has stressed that he was never inebriated during filming, he did admit, to Britain's BBC Radio 2 on January 22, that his memory of those times is lacking.

Host Chris Evans asked Perry which his least favorite episode of Friends was.

"I think the answer is, I don't remember three years of it, so none of those. I was a little out of it at the time. Somewhere between seasons 3 and 6," he admitted.

Perry attended rehab twice during his time on the hit TV show, in 1997, and again in 2001. He has since opened his own sober-living facility for men, called the Perry House, in a Malibu beach abode where he once lived.

Perry told the Hollywood Reporter last year that his work helping addicts is the thing that gives him most pride. “I’ve had a lot of ups and downs in my life and a lot of wonderful accolades,” he told the outlet, “but the best thing about me is that if an alcoholic comes up to me and says, ‘Will you help me stop drinking?’ I will say, ‘Yes. I know how to do that.’”

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