Friend, vomiting, diarrhea and anorexia can be caused by many different conditions. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, in a puppy common causes are: Dietary indiscretion, intestinal parasites, ingestion of a foreign body, infections, etc. to name a few causes. To determine the exact underlying cause she will need to be seen by family veterinarian for a hands on examination. In the meantime in any case of vomiting or diarrhea the first thing to do is give the gastrointestinal tract 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 1/4 tablet every 12 hours for the next 2-3 days. You can buy Pepcid AC over the counter in any pharmacy.
2- Give her a teaspoon of honey, pancake or karo syrup directly into her mouth. Then, no food or water for 3-4 hours. Need to give her gastrointestinal tract time to rest.
3- After 3-4 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.
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