Fans of the High School Musical actor, 25, were shocked recently when it was reported that he'd spent time in rehab for 'cocaine addiction'.
But, if his Twitter account is anything to go by, Zac is now on the road to recovery and looking fit and well.
Sending a message out to all his supporters, Zac posted a picture of a recent holiday in Peru.
On the summit of the country's famous landmark Machu Picchu, Zac is smiling and shows no sign of any recent turmoil.
Alongside the photo, he wrote: "Hey guys! Just returned from an incredible trip to Peru with my dad and wanted to thank you all for your support these past few weeks…means the world to me. Love you guys! – Z."
Hey guys! Just returned from an incredible trip to Peru with my dad and wanted to thank you all for your support the… http://t.co/VJShhgWTuE— Zac Efron (@ZacEfron) September 27, 2013
It was claimed earlier this year that Zac was enrolled in two rehab stints five months ago after 'a major relapse'.
The actor was spotted on his backpacking trip around Peru earlier this month, and was seen happily posing for pictures with devoted fans.
His loyal fan base can see him back on the big screen in upcoming comedy, That Awkward Moment, which centres around a group of young guys who vow to stay single.
What do you think of this story? Tell us what you think in the comment box below.