The Transformers star has been arrested for public intoxication twice in as many years, including in 2014, when he was infamously jailed for causing a ruckus during a Broadway performance of Cabaret.

As part of his punishment, he was ordered to enrol in an alcohol treatment programme, which he completed last year (15).

It proved to be a huge turning point for Shia, as the star hasn't touched alcohol in over a year and has been attending support group meetings at Alcoholics Anonymous in a bid to stay sober.

"I got a Napoleonic complex," he tells Variety of the toll alcohol took on him. "I start drinking and I feel smaller than I am, and I get louder than I should. It's just not for me, dude."

"You don't touch it," he adds. "Alcohol or any of that s**t will send you haywire. I can't f**k with none of it (sic). I've got to keep my head low."

LaBeouf, 30, was first exposed to drugs and alcohol at an early age by his father Jeffrey.

"There were drugs everywhere - marijuana, cocaine, heroin," he recalls of spending time with his dad as a youth. "(My father) gave me my first joint when I was probably 11 or 12."

Notorious method actor Shia confesses in addition to the influence from his upbringing, his career in Hollywood contributed greatly to his drinking habits.

His work in movies such as Wall Street 2, the Transformers franchise, and Indiana Jones and the Kingdom of the Crystal Skull were slammed online by some unhappy fans, and reading the scathing social media comments sent him over the edge.

"I didn't like going in public, because I had to face my failures constantly," he shares, admitting his perceived career defeats led him to increase his alcohol consumption. "Part of it was posturing. I never knew how to drink. I never liked to drink, but I knew you had to drink. It was a weird post-modern fascination with the f**k-ups. When I met (recovering addict) Robert Downey Jr., I was like, 'Man, you got all this f**king texture. How do I do this? How do I build texture?'"

Ultimately, Shia appreciates how alcoholism has impacted his career, as the roles he's currently receiving are more fulfilling than ever.

"I don't think I'd be working with the directors I've been working with if I had not f**ked up a bit," he notes. "They wanted a f**king fireball. They wanted a loose cannon. I'm learning how to distill my 'crazy' into something manageable, that I can shape and deliver on the day."

He concludes: "I was an open wound bleeding on everything."