I am sorry that you are having this problem with your dog. If he has vomited 7 times in the last 2 hours and is lethargic (lying around) we need to rule out things like ingestion of a foreign body, pancreatitis, etc. to name a few causes. If you have access to ER vet I would have him checked tonight. If you do not have access to ER vet this is what you can do until he is seen by your vet in the morning:
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 8-12 hours. Need to give his gastrointestinal tract time to rest.
3- After 8-12 hours offer a small amount of water. Wait half hour, if no vomiting, he can continue to have water. Keep him off food for 16-20 hours, then, 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 in the morning.
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