Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
I am glad to hear screening lab work was normal and I assume this included a complete blood count, chemistry profile, thyroid screening, stool exam and urine check. This helps us rule out a lot of problems that could lead to vomiting. However, given that he is still experiencing this indicates there is a persistent problem.
Possible considerations that could cause this type of increase in vomiting might include inflammatory bowel disease, foreign object trapped in the digestive tract, food allergy, chronic pancreatitis, cancer (digestive tract in particular), and there are other things to consider. Unfortunately this is going to require a bit more diagnostic testing to rule out some of these key concerns. The starting point would be to do radiographs (X-rays) as a general screening +/- ultrasound of the abdomen. I would also highly recommend submit a gastrointestinal profile that checks for pancreatitis (PLI test) and vitamin B levels (cobalamin and folate). If nothing is found then the test after this would be to get samples of the digestive tract to screen for inflammatory bowel disease (endoscopy or surgical).
In the meantime what can you do? If not already doing I highly recommend a trial with something simples such as Pepcid AC (famotidine) to reduce stomach acid and in many cases may stop vomiting- you give half of the 10mg tab once daily for cats. NO bad side effects anticipated and you can easily purchase this over-the-counter at any people pharmacy. Second, is to consider doing a hypoallergenic diet trial. This is not as simple as switching brands or using one of the "sensitive" diets at the pet store. You need to work with your vet to do a serious hypoallergenic trial. We usually do either a hydrolyzed diet (such as Hill's a/d or Purina HA) or a limited ingredient diet. This helps us rule out food allergy as the culprit. Third, I highly advocate starting Sam on a probiotic supplement to encourage better digestive tract health. The best two for cats are Fortiflora (made by Purina) or Proviable. Your vet should have one of these on-hand.
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