The actor, who has a history with substance abuse, told the Guardian that he turned to the drug while he was a part of a surf group called the Cito Rats.
"It was Santa Barbara. It was the 80's. It was punk rock. You either had the children of rich, neglectful parents or children of poor, neglectful parents, so it was a mix. But we basically grew up the same way. I've never seen a group like that before or since.
Brolin, 46, who got divorced from wife Diane Lane last year, had earlier said that getting involved in drugs during his teen years saw him stealing car parts.
The actor was back in rehab last year after he made headlines for getting involved in a drunken bar fight.