Zac Efron
Zac Efron was spotted looking lean and healthy at the Toronto International Film Festival (TIFF). Efron was there to attend the premiere of his latest movie ‘Parkland’, a drama flick based on the assassination of John F. Kennedy.Jason Hargrove / Flickr

Zac Efron, the lead actor of teen flick "High School Musical" has had his share of troubles. Several sources reported earlier that the actor spent five months in rehab for alcohol abuse. However, word is now out that his stint in the rehabilitation center was for issues far graver than just a "drinking problem".

Efron was battling "Cocaine addiction" issues, reports Hollywood Life. The "17 Again" star was not only doing Coke but was also dipping into Molly- a pure form of Ecstasy, a popular drug used in rave parties.

Apparently, Efron's struggle with drugs started sometime in April, during the shooting of 'Neighbours'. He was absent for many shoots and sources claimed that everybody knew Efron was into drugs.

"It was common knowledge he was struggling with cocaine," TMZ quoted a source.

Earlier in 2013, Efron and his friends are said to have gone on a 'coke rager' in a hotel room at the MGM Grand in Las Vegas and caused $50,000 in damages.

The news still remains a rumour as no official confirmation on the issue has been received yet. Efron's rep didn't respond to messages.

It seems the stint at the rehab has rejuvenated Efron. He now looks sober and clean. 

"He's healthy, happy and not drinking. He's taking time to focus on working," a source told E! Online

He was spotted looking lean and healthy at the Toronto International Film Festival (TIFF). Efron was there to attend the premiere of his latest movie 'Parkland', a drama flick based on the assassination of John F. Kennedy.

Check out the trailer of 'Parkland' below:

Tinsel town is no stranger to drug addiction. More recently, Glee heartthrob Cory Monteith died after overdosing on Heroin and alcohol in a hotel room in Vancouver, Canada, July 13.

Check out a list of famous celebrities who died of drug overdose, here.