"Aside from the recent vomiting due to the de-wormer, has she had diarreah and or vomiting often in the past especially since the weight loss?"
She's had occasional diarrhea and vomiting, but it mostly died down after she recovered from the antibiotics given to her during her surgery. I think most of her vomiting since then has been hairballs. This is what I found online on IBD, is it an accurate source?
http://www.vet.cornell.edu/fhc/brochures/ibd.html
She also had an eye that was occasionally cloudy in the week or two before she went to the vet. The dewormer seemed to make it better, so is it possible she had worms as well? Thanks for the info.