Friend, I doubt the vomiting and diarrhea you are seeing now is related to the tampon she threw up 2 days ago, there is something else going on. It is possible she could have another foreign body causing the vomiting and diarrhea. Other possible causes are: Infections, intestinal parasites, etc. to name a few causes. Regardless of the cause if she has been vomiting and diarrhea for the last 2 days we really need to be concern about hydration. Unfortunately we are very limited as to what you can do at home. I would strongly recommend having her checked this morning by family veterinarian. They will start her on IV fluids, anti emetics, etc. In addition, they will do some testing to determine the exact cause for the vomiting and diarrhea. If she goes untreated this could be fatal. In the meantime, this is what you can do:
1- Do not give things like Pepto Bismol or imodium. Start her on Pepcid AC (famotidine) 10mg 1/4 tablet every 12 hours. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 4-6 hours. Need to give her gastrointestinal tract time to rest.
3- After 4-6 hours offer a small amount of water. Wait half hour, if no vomiting, offer small amount of rice (50%) and boiled boneless chicken or ground beef (50%) 4-6 times a day. Keep on this diet for several days then wean into regular diet.
4- Follow up with your family veterinarian for a hands on examination, supportive care, xrays, fecal analysis and blood work. If cost is a concern look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost.
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