Paula Abdul. (AP File)

Pop star-turned-American Idol judge Paula Abdul has hit back at new reports she's often high or drunk on TV, insisting she just falls asleep easily.

The tired Straight Up singer has fought rumours about her sobriety ever since she appeared to be drunk on a TV news show last year, slurring her words and appearing to be out of it.

And the negative press didn't end there - thanks, in part, to bizarre appearances on Idol and her reality TV show Hey Paula, during which she appeared to struggle to stay awake during some scenes.

She tells WENN, "Firstly, I've never been drunk in my life, I don't like it (alcohol). It's not my thing. Spending money on clothes and shoes that's another thing.

"And you can check my medical records, I was never on (painkillers) Oxycontin or Vicadin or anything like that. I was on nerve medicine and anti-inflammatories (for a neck injury she suffered in 1992)."

But she understands how certain behaviour patterns have fuelled the rumours about her: "Because I'm falling asleep and a camera is on me."