Lindsay does “things” in the bathroom

Seems some of Lindsay Lohan’s extracurricular activities are catching up with her. She was caught red-handed doing an unspecified something at a recent Calvin Klein party last week, as the New York Daily News reports:
According to witnesses, a gentleman identified as “a gay friend” entered the ladies’ room…
“He was saying out loud in explanation, ‘I’ve got to take care of my friend,’” says a witness.
“He pushed open Lindsay’s bathroom stall, where she was bent over. Lindsay jumped up when she realized the door was open and the onlookers just said, ‘Whoa.’”
Some people got the distinctly wrong impression of what she was doing.
But Lindsay’s rep explained: “Her friend went into the ladies’ room, which the attendant okayed, to zip her dress.”
I’m confused. So “zip her dress” is code for sticking her finger down her throat to relieve herself of all that pesky food she has to eat to keep herself in size 2’s? Or is “zip her dress” street slang for snorting an entire eight-ball of coke? But why would she have to bend over for that? Never having indulged in either activity, I just can’t say. So my guess is she was throwing up, based on absolutely nothing but my gut feeling, by which I mean complete speculation unsupported by any facts whatsoever.
Shit, someone help me out! What do you think she was doing in there that elicited a “whoa” from onlookers?
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