Friend, the maggots are not going to be harmful especially if he did not ingest any of the bacon or maggots. Other possible causes for his symptoms are dietary indiscretion, intestinal parasites, ingestion of a foreign body, infections, etc. to name a few causes. In any case of vomiting and diarrhea the first thing to do is give the gastrointestinal tract 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 1/2 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.
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 or diarrhea after doing the above he will need to be seen by your family veterinarian for a hands on examination.
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