Friend, vomiting and diarrhea can be caused by primary problems occurring in the gastrointestinal tract or secondary to a systemic disease. Buddy being anorexic and lethargic is simply a consequence of not feeling well. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, common causes are: Dietary indiscretion, ingestion of a foreign body, infections, kidney or liver disease, etc. to name a few causes. In this case to determine the exact underlying cause Buddy will need to be seen by a veterinarian for a hands on examination, blood work, urinalysis and xrays as initial screening test. Treatment will be based on exam and test results. If possible, I would have him checked today he may benefit from supportive care (IV fluids, anti emetic, etc.) pending test results. If you can not have him seen today by a vet this is what you can do:
1- Do not give things like Pepto Bismol or imodium. Start him on Pepcid AC (famotidine) 10mg tablet every 12 hours. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 3-4 hours. Need to give his gastrointestinal tract time to rest. Keep him indoors in a cool room when fasting.
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. If possible blend the food with some water and force feed him a small amount with dropper.
4- Follow up with your family veterinarian for a hands on examination in the morning. 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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