Thanks for the reply. If you haven't changed your feeding schedule and i/d seems to have resolved the vomiting problem, it does suggest that food might be the culprit. I note that you normally feed Fancy Feast. I wonder whether there might be something up with Fancy Feast foods at the moment? A number of cats that came out of remission recently were being fed Fancy Feast, and I've also seen a report elsewhere of another FF-fed kitty who has diarrhoea at the moment. Of course, all these incidents may be unrelated but the coincidences seem a little odd to me.
If you try reintroducing FF I'd suggest getting some new cans because they might be from a different batch. If that works OK and the vomiting doesn't return, you might then try feeding some of the older cans (i.e. the ones you currently have) and if the vomiting problem comes back then I'd set that can and any other cans bought at the same time to one side and report the batch number(s) to the manufacturer. (And perhaps post a note of the batch numbers on Feline Health so that other members will know there might be a problem with the food.)
Mogs
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