Catherine Zeta-Jones treated for bipolar disorder

Catherine Zeta-Jones's representative has revealed that the star sought treatment for bipolar disorder at a health facility.

Bipolar disorder, otherwise known as manic-depressive disorder, brings about unusual changes in mood and energy that can result in manic episodes - an overly excitable state - or depressive episodes - a state of heightened sadness.

A representative for the actress released a statement saying: "After dealing with the stress of the past year, Catherine made the decision to check in to a mental health facility for a brief stay to treat her Bipolar II disorder."

The statement continued: "She's feeling great and looking forward to starting work this week on her two upcoming films."

Bipolar II disorder is not regarded to be as severe as Bipolar I disorder. The actress spent five days in the facility, according to People.

A source close to Zeta-Jones said that the star has had a stressful year, largely due to her husband Michael Douglas being diagnosed with throat cancer.

"Catherine has had to deal with Michael's illness and that's been hard. She went in for a few days because she's about to start working, and wanted to make sure she's in top form, which she is," the insider explained.

Zeta-Jones recently insisted that Douglas is making a speedy recovery following his cancer battle.