Friend, I know it is very scary to see your dog vomiting; the odor is directly related to the stomach content being there for a while, this is not an indication of anything bad. The big question is: Why does he have diarrhea and vomiting? Vomiting and diarrhea 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: Dietary indiscretion, intestinal parasites, ingestion of a foreign body, infections, etc. to name a few causes. In any case of vomiting or diarrhea 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 him on Pepcid AC (famotidine) 10mg tablet every 12 hours for the next 2-3 days. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 6-8 hours. Need to give his gastrointestinal tract time to rest. Keep him indoors in a cool room when fasting.
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 him on this diet for several days then wean him into his regular diet.
4- If he continues to vomit after doing the above he will need to be seen by your family veterinarian for a hands on examination.
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