Mariah Carey admits battle with bipolar disorder, says she's no longer in denial

She's been called a diva, but what Mariah Carey's critics may not have known is that the singing star has been dealing with bipolar disorder for nearly 20 years.

Carey is making her diagnosis public in the hopes of breaking the stigma of this mental health issue. Mental health experts said Carey coming forward will help many.

Carey told People Magazine, "Until recently, I lived in denial and isolation and in constant fear someone would expose me. It was too heavy a burden to carry and I simply couldn't do that anymore."

As the name suggests, patients deal with emotions that are polar opposites. USC's Dr. Susie Park is a board certified psychiatric pharmacist who helps treat bipolar disorder.

"Fluctuations in feeling irritable, but then happy and pleasant in one moment, and perhaps a few minutes or hours or days or weeks later feeling very down and depressed," she said, "The cause is not clearly known, but we know there can be imbalances in things like serotonin and norepinephrine."

People with bipolar 2 disorder have hypomanic periods, but the depressive episodes can last longer. "Which can then lead to if untreated things like suicidality, increased episodes of attempts in suicide, decreased functionality," Park said.

Medical experts say both forms of bipolar disorder can be treated with mood-stabilizing medications such as lithium and anti-depressants. Patients can go on to live full, productive lives.

"It's really no different than someone having diabetes who needs to be on glucose-lowering medications to make sure that their symptoms don't come back," Park said.

For those who need more information about dealing with bipolar disorder, Park suggests people go to www.cpnp.org and www.nami.org.

Carey told People Magazine, "I didn't want to carry around the stigma of a lifelong disease that would define me and potentially end my career. I was so terrified of losing everything."

She's now getting treatment, including medication, and wants to continue what she loves to do which is writing songs and making music.