Paula Abdul has finally come up with an excuse for her �out-of-it� onscreen appearances � apparently it�s down to the painkillers that she takes for a neck injury.

Paula claims to have been diagnosed with reflex sympathetic dystrophy (RSD), a chronic neurological disorder that causes severe pain.

"It can come and go at any time but I no longer have the intense nerve pain that is associated with RSD, thank God,� she tells OK! magazine.

"I have four titanium plates in my neck. I've had 14 surgeries over the years. I had an operation the same evening as the first season finale of American Idol."

Paula says that her injuries, caused by a car accident and then made worse by an emergency plane landing, are treated with anti-inflammatory medications.

"If I appear exhausted on television, it's because I am!" she says. "I have a lot of sleepless nights because I'm in so much pain. I was taking far more medication on earlier seasons [of Idol], and nobody said anything. I try to say something and I stumble, and that's what people have picked up on. I'm not polished."

"I'm sick of it. I've never been drunk. I don't do recreational drugs. It's defamation of character," she insists.

Far be it for us to �defame� Paula�s character, but she must be taking an awful lot of painkillers to achieve that swaying, drug-addled demeanor.