One of the most difficult moments for a celebrity is having to make a trip to rehab, and unfortunately, it's happened to more famous people that some might be surprised to hear.

Amanda Bynes Resurfaces On Twitter After Rehab

On Tuesday, it was announced that Robin Williams was going to be checking into a treatment facility. According to TMZ, the actor will be staying there for several weeks.

"After working back-to-back projects, Robin is simply taking the opportunity to fine-tune and focus on his continued commitment, of which he remains extremely proud," a rep for Williams told the site.

Dean McDermott Rehab & Cheating Rumors

Another actor who went to rehab that may have come off as quite a shock for some was High School Musical Star Zac Efron. Rumor had it, he was there for alleged substance abuse and alcohol, according to Deccan Chronicle. But apparently there turned out to be some positivity in it, according to the actor.

"I am so happy now and I feel like I am in a great place," Efron said. "It was an interesting year and I learnt so many things, but the best part of it was being able to reflect upon my experiences and what I had learnt about myself and the kind of man I want to be."