If you want to hide a raging cocaine problem, all you have to do is tell people you’re going to rehab for a drinking problem. According to TMZ’s latest report, that’s what Zac Efron did when he entered rehab “roughly 5 months ago” and it was “insinuated” he was being treated for alcohol. But Charlie St. Cloud was hiding a much bigger secret on the set of Seth Rogen's new film Neighbors:

Sources tell us Zac — who also starred in the movie — was a no-show on a number of days. As one source connected with the film tells us, "It was common knowledge he was struggling with cocaine."

Three other sources confirm ... Zac's problem was rooted in cocaine, but say he also dabbled in Molly — a pure form of Ecstasy, and a popular drug in clubs and raves.

In response to the accusations, Efron’s rep told TMZ: “Don’t think we’ll be making a comment.”

Earlier this week, Efron—who has now finished treatment for whatever his problems may be—told E!, “I’m good, real good.”

[Image via Getty]