Robert Downey Jr. wasn't always a sober man.

The "Iron Man" actor pops out of a window on the cover of Vanity Fair's October 2014 issue and opens up about his past struggles with drugs. The 49-year-old actor speaks out about his eldest son, who was recently arrested for cocaine possession in late June, and could be facing a maximum sentence of three years and six months in prison.

"He's his mother's son and my son, and he's come up the chasm much quicker than we did," the actor said. "But that's typical in the Information Age; things get accelerated. You're confronted with histories and predispositions and influences and feelings and unspoken traumas or needs that weren't met, and all of a sudden you're three miles into the woods."

He added: "Can you help someone get out of those woods? Yes, you can. By not getting lost looking for them. Pick a dysfunction and it's a family problem."

Downey Jr. reportedly started abusing drugs by getting high as a kid - a hobby that he continued even after making it big in Hollywood. In 1996, the actor was pulled over for speeding and police found heroin, cocaine and crack cocaine in his car. An unloaded .357 Magnum was also discovered under the passenger seat.

In 1999, the actor told the court that he had been addicted to drugs since age eight because his father, who was a fellow addict, had frequently supplied him with drugs. He was forced to check into rehab several times, and even broke out of two facilities. He was later sentenced to 36 months in jail, though he served just under a year.

"Job one is get out of that cave," Downey Jr. said. "A lot of people do get out but don't change. So the thing is to get out and recognize the significance of that aggressive denial of your fate, come through the crucible forged into a stronger metal. Or whatever."

He said: "It's funny: five years ago, I would've made it sound like I'm conscious of my own participation in seizing the similarities. But so many things have become less certain. I swear to God. I am not my story."

Downey Jr., who is Hollywood's highest paid actor, credits his 10-plus years of sobriety to his wife, film producer Susan, who is pregnant with the couple's second child.