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.
This really sounds quite concerning for Emily. Given her age and the severity of her vomit/diarrhea I am worried she will become profoundly dehydrated. Therefore, the absolute best for her is to be seen on emergency today.
As far as cause for this there is a long list of potential causes since vomit/diarrhea are very nonspecific; this might include anything from ingested foreign object or unusual food item that has upset the system to organ issue (liver, kidney) to pancreatitis to an endocrine issue (e.g., diabetes, hyperthyroidism) intestinal parasites to cancer. To try to narrow down this list would require an examination followed by some testing that at a minimum might include a CBC, chemistry profile, urine check, thyroid screen, fecal check +/- radiographs (X-rays).
I can offer you a few things to try at home, but I really am quite worried by what you report and recommend you take her to be seen. If this is absolutely not possible and she was my patient I might recommend you try:
1) Withhold food for a few hours but no more than 8 since I am worried about dehydration. Then tempt her to eat with something bland such as pureed people baby food (chicken variety in particular).
2) Give famotidine 10mg at 1/4 tablet every 24 hours for nausea/vomit. This is not a potent anti-vomit medication but can help tremendously in many cats. You should be able to find this medication at any pharmacy over-the-counter. It has no bad side effects and does a great job to settle stomach acid and reduce nausea.
3) Peptobismol liquid: Give 0.5 ml (1ml = 1 cc) by mouth every 12 hours for diarrhea. This medication must be given 1 hour after any other medication as it will coat the system and can potentially prevent absorption of other medications.
4) Probiotic supplementation: Start a probiotic such as one made for cats (Proviable or Fortiflora) or you may use culturelle as made for people (1/2 of an adult capsule daily). Or if you cannot get any of those products then give 1/2 tsp of plain yogurt once daily.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
Please let me know if for any reason you need further clarification, have more questions, or were expecting a different type of answer.
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