Mandy, vomiting 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: A simple gastritis, pancreatitis, dietary indiscretion, ingestion of a foreign body, infections, or even part of a systemic disease, etc. to name a few causes. The fact that Winnie is an older dog it is important to rule out systemic diseases like: Kidney, liver, tumors, hormonal disorders, etc. To determine the exact underlying cause she will need to be seen by family veterinarian for a hands on examination, blood work and urinalysis as initial screening test. 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 Zantac (ranitidine) 75mg 1/4 tablet every 12 hours. You can buy Zantac over the counter in any pharmacy.
2- No food or water for 4-6 hours Need to give her gastrointestinal tract time to rest. Keep her indoors in a cool room when fasting.
3- After 4-6 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.
4- Follow up with your family veterinarian for a hands on examination.
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