Friend, I don't believe the vomiting is related to the heat or by having a milk bone once a day. I will not be able to pinpoint the exact underlying cause without a hands-on examination and some testing, I am sorry. But, common causes are pancreatitis, gastritis, dietary indiscretion, ingestion of a foreign body, infections, or even part of a systemic disease, etc. to name a few causes. To determine the exact underlying cause she will need a hands-on examination by your vet, x-rays and blood work as an initial screening test. Treatment will be based on exam and test results. In the meantime, in any case of vomiting, 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 her 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 her 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 on this diet for several days then wean into regular diet.
4- Follow up with your family veterinarian for a hands on examination.
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