Friend, I really do understand your financial constraint being a student. But, if Cinnamon has been vomiting for 3 days and not eating or drinking I am really concern about his hydration, this could potentially be fatal without supportive care of IV fluids, anti emetics, etc. I am going to make some recommendations below. But, I recommend you try to get him into your local ASPCA or Shelter where they often offer veterinary services at a lower cost. Besides supportive care he will need some testing to determine the exact underlying cause for the vomiting. In the meantime this is what you can do:
1- Do not give things like Pepto Bismol or imodium. Start him 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 3-4 hours. Need to give his gastrointestinal tract time to rest so that when you offer water and food he does not vomit.
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. Continue to give water with a dropper as long as he is not vomiting.
4- Follow up with a veterinarian for a hands on examination and supportive care.
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