Two and a Half Men star Charlie Sheen voluntarily checked into an undisclosed rehabilitation center on Friday, a rep for the actor tells TVGuide.com.

"He is most grateful to all who have expressed their concern," the rep says.

Charlie Sheen released from hospital

With Sheen's absence, Two and a Half Men will be going on production hiatus. "We are profoundly concerned for his health and well-being, and support his decision," CBS Entertainment, Warner Bros. Television and series executive producer Chuck Lorre said in a joint statement on Friday.

On Thursday, Sheen was admitted to Cedars-Sinai Hospital in Los Angeles with what his rep described as "severe abdominal pains." The 45-year-old actor was released from the hospital later that day and was expected to return to the set of Two and a Half Men on Tuesday.

The actor told a source quoted by Extra: "I'm not dying." His friend, Steve Brodersen, told the TV newsmagazine Sheen's abdominal pain was the result of a hernia injury, made worse when Sheen laughed too hard at the TV.

CBS President: "We have a high level of concern" for Charlie Sheen

Earlier this month, CBS President Nina Tassler said they "have a high level of concern" for Sheen, whose personal life has long been a source of controversy.

In recent months he's appeared regularly in the tabloid headlines. Police officers were called to Sheen's allegedly destroyed New York hotel room last October, he's filed for divorce with his wife Brooke Mueller, and he reportedly went on a bender with multiple escorts early in January.