Catherine Zeta-Jones has checked into rehab once again for her bipolar II disorder. People magazine reported the 42-year-old starlet was “proactively” seeking treatment at a mental health facility.

"Catherine has proactively checked into a health care facility," her rep, Cece Yorke, told People. "Previously Catherine has said that she is committed to periodic care in order to manage her health in an optimum manner." 

An insider told the celebrity magazine that Zeta-Jones has entered rehab so doctors can monitor her medication.

"There was no big problem," the source said. "This was just a good time to do it. She is in between projects. This has always been part of the plan. She would manage her health. She is vigilant about it." 

TMZ sited a source that said seeking treatment was “maintenance" for the Oscar winner.

The "Chicago" actress did a 2011 stint in a Connecticut rehab, the site reported, for her disorder, which can cause high and low mood swings with bouts of depression.

"This is a disorder that affects millions of people and I am one of them," Zeta-Jones told People at the time. "If my revelation of having bipolar II has encouraged one person to seek help, then it is worth it. There is no need to suffer silently and there is no shame in seeking help." 

Everything reportedly seemed OK with the Hollywood star when she walked the carpet with husband Michael Douglas for Film Society of Lincoln Center’s 40th Annual Chaplin Award Gala honoring Barbra Streisand.

But on Saturday, Douglas went stag to the White House Correspondents Dinner.

Zeta-Jones is expected to complete a 30-day program, TMZ said.

Her last silver screen flick, “Side Effects,” also featured Jude Law, Channing Tatum and Rooney Mara. It focuses on the unexpected side effects of a drug used to treat depression.

Her newest film, “Red 2,” also starring Bruce Willis, will hit theaters July 19.