Zac Efron didn't just go to rehab once, but had two stints in rehab for coke addiction this year, TMZ reports.

Zac Efron went to rehab for the first time for cocaine addiction, and then returned after a relapse, according to TMZ.

Sources told the website that Zac has been doing coke for more than 2 years, and was also into Molly, a form of the drug ecstasy.  In March, Zac Efron attempted to get professional help for his addiction to coke, and left California to stay in a private residence where he received intensive outpatient care for several weeks.

But it reportedly wasn't enough. In April, Zac Efron returned to Los Angeles and began shooting Seth Rogen's film "Neighbors."  

During filming, Zac relapsed. Efron allegedly was not showing up on the set, due to his addiction, TMZ reports.

Once filming wrapped up, sources say Efron went back to rehab for a second go at outpatient care.

TMZ reports there are four main reasons why our beloved 25-year-old "High School Musical" actor became addicted to coke and had to turn to rehab.

Zac reportedly had "girl issues," and though no specifics were given by sources, one thing TMZ notes is that this had nothing to do with Efron's break-up with Vanessa Hudgens.

Zac had been hanging around with "a bad group of friends" too, who introduced him to the world of cocaine. Fortunately, Zac has recently stopped spending time with them in the last few months.

Zac also is allegedly upset about his movie career, which has never reached the same success after "High School Musical."

Lastly, Zac has significant issues with his parents, who are trying to control his life and decision-making, TMZ adds.