"I was so hung over for that whole movie," McCarthy said of 1986's "Pretty In Pink" with Molly Ringwald. "I'm thinking 'God, I got a headache. I am just dying here. I got to go lie down.' But on film, it came across a certain way," McCarthy said, talking about his alcoholism for the first time on last Friday's ABC New's "20/20."
"A good alcoholic is a very secretive person," McCarthy said. "I was quite effective in some of those films. ... It took a while for alcohol to really sort of kick my ass, which it ended up doing completely."
McCarthy said he crossed the line sometime in the late 1980s or early 1990s.
The actor, who is now sober, stars in ABC's "Kingdom Hospital."
Notable deaths of 2014 [PHOTOS]
Polly Bergen, Emmy Award-winning actress, dies