The Oscar-winning actress, 25, made the shocking revelation when playing a game of "True Confessions" with Jimmy Fallon and John Oliver on "The Tonight Show Starring Jimmy Fallon", reported Ace Showbiz.
"I once took an Ambien before filming a scene in 'The Hunger Games'," she said, letting the two funnymen guess whether she told a truth or a lie.
"Were you sleeping in this scene?" Fallon asked.
"No, in fact, I was dancing," Lawrence replied.
"I woke up and I thought it was something else, it was like normal to take it," Lawrence further explained.
Both Fallon and Oliver guessed that it was true.
"It's plausible, it's reckless, I kind of like it, if it's not true I'm going to be very sad," Oliver reasoned. And Lawrence admitted that it did really happen.