Pop sensation Mariah Carey has revealed she is finally receiving treatment for diagnosed bipolar disorder despite being in denial over her condition for a number of years.

Mariah CareyMariah Carey has opened up about her mental health problems

The singer and songwriter - who has been in the pop business for three decades - admitted she was first diagnosed in 2001 after a breakdown but failed to seek treatment until recently.

The star has said she is no longer living in "denial and isolation" after being treated.

Speaking to People magazine that she "didn't want to believe it" when she was diagnosed in 2001 after receiving hospital treatment for a physical and mental breakdown.

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She said: "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."

The 48-year-old is now in therapy and taking medication for bipolar II, which involves periods of depression and hypomania, and often involves irritability.

Mother-of-two Carey - who shares custody of her twins Monroe and Morocco with ex-husband, Nick Cannon - said the medication is having a positive effect and is not making her feel too tired or sluggish.

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She said: "I got back to doing what I love - writing songs and making music."

She said that she first thought she was suffering with "normal insomnia" as she could not sleep and was "working and working and working".

The star said she was "irritable and in constant fear of letting people down" and that she later learned she was "experiencing a form of mania".

She said: "Eventually I would just hit a wall. I guess my depressive episodes were characterised by having very low energy."