Cece Yorke, a rep for the actress, tells ET, "Catherine has pro-actively checked into a health care facility. Previously, Catherine has said that she is committed to periodic care in order to manage her health in an optimum manner."
Bipolar II is a milder form of the disorder known to cause mood swings and erratic behavior.
Zeta-Jones first announced her diagnosis in 2011, undergoing treatment at Silver Hill Hospital in Connecticut. At the time, Zeta-Jones' rep told ET that the "Chicago" star made the decision to enter treatment "after dealing with the stress of the past year."
The 43-year-old Oscar winner can next be seen in "Red 2" alongside Bruce Willis, Helen Mirren, Anthony Hopkins and John Malkovich. The action sequel opens July 19.
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