Dozer, I am sorry your dog has diarrhea and does not want to eat, I am sure this must worry you. In response to your question, when we see diarrhea and vomiting these are symptoms of either primary disorders affecting the gastrointestinal tract or secondary to a systemic disease. His lack of appetite is simply because he does not feel well. This 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, ingestion of a foreign body, infections, or even part of a systemic disease to name a few causes. This is what you can do:
1- Do not give things like Pepto Bismol or Imodium. I would also stop Metacam until GI issues have resolved. Start him on Pepcid AC (famotidine) 10mg every 12 hours. 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. Then, offer a small amount of water followed by a diet of rice (75%) and boiled boneless chicken or ground beef (25%) until the stool is back to normal then wean him back into the regular diet. Keep him indoors in a cool room and no exercise when fasting.
3- Supplement with a probiotic, these are friendly bacteria that help with regularity. You can buy this over the counter in any pet store.
4- If after doing the above you do not see improvement within 24 hours I would have him checked by your family veterinarian for a hands on examination.
5- If he continues to vomit despite fasting; Or, if you see bloody stool, lethargy, abdominal swelling, pale gums, etc. have him checked by ER veterinarian, do not wait.
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