Hanks called Efron's effort in seeking treatment a "courageous step to take", reported E! News.
"I'm not hip about (efron's problem) but I think anybody who says, 'Hey, maybe I should go work on this,' more power (to him)," Hanks said.
Efron broke his silence following his rehab revelation just last week, posting a picture from a trip to Peru he just took with his dad and thanking fans for their "support these past few weeks.