Dennis Quaid used cocaine "pretty much on a daily basis" during the 1980s.
The 64-year-old actor battled with an addiction to the illegal substance over 30 years ago, and has said growing up in a time where "there was a completely different attitude" toward cocaine use made it easy to succumb to bad habits.
He said: "It was even in some movie budgets. I was basically doing cocaine pretty much on a daily basis during the '80s. I spent many, many a night screaming at God to 'Please take this away from me and I'll never do it again, cause I've only got an hour before I have to be at work.' Then at 4 o'clock in the afternoon I'd go, 'Oh it's not so bad.'"
But the 'Parent Trap' star had a "white light experience" which caused him to enter rehab for his addiction, after he realised he was beginning to lose everything around him.
He added: "I had what I call a white light experience where I saw myself either dead or losing everything that meant anything to me."
Dennis was married to fellow Hollywood star Meg Ryan - with whom he has 26-year-old son Jack - when he entered rehab, and whilst he says his romance with the star was "the most successful" of his life, he felt as though he "disappeared" because of Meg's growing fame.
Speaking on the 'Today' show, he said: "[That was] the most successful relationship of my life. When we met I was the big deal, [but then] we'd go out on the streets of New York and it would be like, 'Meg! Meg!' And I have to admit it, I actually did feel like I disappeared. I didn't think I was that small, but I was. It was a growth opportunity - I learned from that."
The 'Day After Tomorrow' actor is now in a relationship with model Santa Auzina, 31, whom he began dating in 2016 after he split from his third wife, real estate agent Kimberly Buffington, with whom he has 10-year-old twins Thomas and Zoe.
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