Cat vomiting

My sister's 1-year-old cat Daisy just threw up twice. I noticed some cat vomit upstairs a couple days ago too, but since we have two cats in the house, I figured it could have been either and since it was only once, there wasnt really anything to worry about. Now I'm getting kind of worried though. She was declawed almost a week ago (my sister's decision, not mine) and has been wearing a cone to stop her from licking her paws. She's had it off twice and went straight for the paws, so we had to put it back on both times. She seems fine now and has come up to cuddle with me on the couch, but I'm really worried about her. I believe she's on pain medication, so could that be causing her to feel Ill of is something else wrong? She's also been behaving sort of like a sick person, laying around a lot and cuddling which she never did much of before. Is it just because she's sore/on medication or could she really be sick?

Sorry to hear about Daisy (on all levels).

It's probably because she is sore that she is acting 'off'.  Also, the medication can cause a stomach upset.

I hope she is on pain meds--which medication?

Is she lethargic (no energy) or sleepy (there is a subtle difference)?

When Ritz is sick she tends to be more cuddly.  Perhaps that is also the case with Daisy.  Would your sister have a better sense of this?

How is the other cat reacting to Daisy (is he/she also declawed)?

How long does she have to wear the cone? Hopfully not much longer. The medication could definitely be making her sick, but she could also be sick with an infection. Are her toes swollen, oozing, or hot? I would definitely call the vet and check with them. It may be normal for her to vomit for a while with the anesthesia. My Chrissy was 'sick' for over a week when she was spayed, she had no energy at all. She did eventually get better, it sure was easier on my males to get neutered!

Excellent point Di and Bob:  how do her toes look, and, any smell?