Vomiting

My cat went on a strict diet 3 month ago, because of sediments in his bladder. He is slowly getting better, but started vomiting about once a week. Looks like undigested kibbles, no other symptoms. Eating otherwise well, drinking lots. No change in behaviour. Should I be worried? Any ideas?

Hello!  I'm pleased that the treatment for bladder sediment appears to be going well.  Did you know that one of the underlying causes for bladder sediment is thought to be stress?  Not just stress - usually stress in combination with other bladder- related factors, factors which may have been helped by the diet, pushing your cat back under the threshold for bladder disease, which is great. Now; everyone at this point says 'I don't think that my cat is stressed at all anyway.'  Indeed, cats haven't evolved the art of looking stressed in  the way that humans and dogs do (actually it may be humans who are less good at reading their signals).   Therefore it is worth your while having a good read about signs / contributing factors to stress in a cat, even if you don't believe your cat to be stressed.  Things like having a choice of several litter trays, not having to cross someone else's 'territory' to get to food or exits - you may be surprised.

Anyway, enough of that - you asked about vomiting.  In the past we use to think that some cats just threw up a lot - that it was normal for them.  We now know this not to be true and think that you are right to be concerned.  We firmly reccommend trying to get to the bottom of sporadic vomiting in a cat - checking for underlying diseases such as pancreatitis, for example, worming well and possibly trying an extremely bland food for a good length of time (at least 6 weeks - your vet will advise if they think this appropriate).

You mentioned drinking lots - this can be a sign of pathology so try to grab a fresh water sample if you can and / or mention it to your vet.

Common possibilities for sporadic, apparently otherwise symptom free vomiting include pancreatitis (which can also be stress linked - my brain that jumps ahead of me wonders about linking it to the cystitis, although there is no evidence).  Also liver disease and cancer as well as food intolerance and some less serious possibilities.   We are glad that you have noticed it and are taking it seriously as a sign.  Your vet, who can meet and examine the patient, is likely to be able to help much better than me.