The 25-year-old actor, who shot to fame in Disney's 'High School Musical' as a teenager, quietly completed a rehab stint earlier this year, thought to be for cocaine and alcohol, reported Us magazine.
"He realised he needed outside help. He reached out for it and is doing great now," a source said.
It has been said the hunky actor acted "erratically" on the set of his raunchy new comedy "Neighbours" and his behaviour concerned his friends and family.
The star sought treatment approximately five months ago and now appears to be back on track with a number of movies due for release over the next year.