In response to your question, vomiting can be caused by 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. Start him on Pepcid AC (famotidine
) 5mg every 12 hours for the next 3 days.
2- No food or water for 8-12 hours, keep him indoors away from the heat during the fasting period.
3- After 8-12 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. Keep on this diet for several days then wean into regular diet.
4- If he continues to vomit after doing the above, he will need to be seen by your family veterinarian for xrays and blood work to determine the exact underlying cause.
Hope the above helps, if you have additional questions I will be glad to answer them.