I am niot sure if this will help or not, but years ago when I ran a home based day care I had a little boy who liked to make himself thow up. Lovely on our shag carpeting
I finally put him in the kitchen (where the floor was lino!), closed the door (and stood right outside, peeking at him to make sure he didn't hurt himself), waited until he was finished, took him out, cleaned him up and basically ignored the behavior. This only happened, I think, one more time and he stopped. He did not get the results he was after.
If you are reinforcing the behavior by giving into it, or, indeed, reacting in any way (positive or negative) the behavior will continue.
See what I have learned after having my kids in therapy for almost three years?
LOL