Friend, I am sorry that Gracie is lethargic and vomiting I am sure this must worry you. In response to your question, vomiting and lethargy are very non-specific symptoms and can be caused by many different medical conditions. It will be difficult for me to determine the exact underlying cause without a hands-on examination and some testing. But, common causes are pancreatitis, dietary indiscretion, ingestion of a foreign body, infections, or even part of a systemic disease, etc. to name a few causes. Unfortunately, we are somewhat limited as to what you can do at home, I am sorry. I would strongly recommend a hands-on examination with a veterinarian, blood work, and x-rays as an initial screening test to determine the exact underlying cause. Treatment will be based on exam and test results. In the meantime, in any case of vomiting the first thing to do is give the stomach time to rest. This is what you can do:
1- Do not give things like Pepto Bismol or Imodium. Start her on Pepcid AC (famotidine) 10mg 1/2 tablet every 12 hours. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 6-8 hours. Need to give her gastrointestinal tract time to rest.
3- After 6-8 hours offer a small amount of water. Wait half hour, if no vomiting, offer a 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. If she continues to vomit after doing the above or you notice pale gums or she becomes more lethargic I would have her checked by ER veterinarian.
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