Mucus is draining into the throat because the body thinks there's an infection perhaps? Probably due to allergies.
It can be a few things.<br />
Acid Reflux<br />
You might asked to be moved, or file a complaint. If it's distracting you that much, and keeping you from your work, I'd think about that approach.
I've always had the same issue. Turns out I've got Asthma. Excess mucus builds up and the only way I can get air into my lungs is to clear my throat. Imagine how your coworker must feel not being able to breathe.
loool my younger brother does is.. and I yell at him.. it really gets on my nerves so bad, like just as bad as someone scratching a board. I feel like I want to punch him in the face and I am not a violent person. It is so offensive to me.
She could very possibly be on drugs. <br />
I know when i was popping pills (cough medicine especially) everyday i ALWAYS had to clear my throat i couldnt talk unless i did it..thats how my friends and boyfriend would ALWAYS know if i was on drugs or not, it was the first signal that i relapsed to my addiction.
I used to have this problem in elementary school, and was teased for it. I also had asthma when I was little. There could be a connection. It would probably be best to try being patient and not saying anything. I remember trying not to, then I couldn't breathe, and had to, then everyone would laugh and comment. It is absolutely humiliating.
Start running your fingernails down your desk or something that will cause a equally irratating noise or whistle the same tune over and over again
Konrad has a point it may be attributed to mucus. Is she a smoker? If she is a longtime smoker, she is right, I think it would be hard to stop clearing her throat. She could replace the throat clearing with the "smokers cough" but that would probably just be as annoying to you.<br />
I would suggest to her to consult with a physician to find the origin of her consistent throat clearing to rule out a medical cause.
Could be mental like ocd or Tourette's syndrome. If she is disabled in such a way there is nothing you can do. If you harass her about it on the job you could face legal repercussions do to laws that protect the disabled.
My late atep-mother had this same condition but her throat clearing came from a hernia in her abdomen.
I'd request to be moved, she probably feels as bad about it as you do.
Maybe she's trying to draw attention to the fact that there's something stuck in your whiskers?