Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
I am so sorry to hear your dog is vomiting. Yes, unfortunately an abrupt diet change can cause gi upset and lethargy so this may require a veterinary visit if we cannot resolve it with basic home care.
First, please remove the water. If there is continued actively vomiting we want to minimize anything orally to stop the nausea and abdominal cramping resulting in vomiting. I know the thought is your pet needs to drink to maintain hydration but if there is actively vomiting even water there is risk of becoming more dehydrated with water intake.
If there is no improvement then please consider having your dog seen by a veterinarian sooner rather than later. They can give injectable medications to bypass the intestinal tract and hopefully get the nausea under control
1- Keep indoors to avoid eating grass/ leaves for 6-8 hours from last vomiting episode
2- Offer a small amount of water (1-2 teaspoons hourly) for a few hours in 6-8 hours
3- Start Pepcid (famotidine) 0.25 mg/ pound every 12 hours OR prilosec (omeprazole) 0.5 mg/ pound daily for the next 3 days with the second administration of water (crushed if needed)
4-If no vomiting, offer small amount of white rice and boiled boneless or ground chicken or ground beef. For example, one tablespoon hourly for a few hours then slowly start to increase the amount while reducing the frequency. Keep on this diet for several days then wean into regular diet.
5- If vomiting continues after doing the above, I would encourage having your family veterinarian perform an examination to determine the next step to getting Lexi comfortable and what exactly the underlying cause is.
Indications your dog should be seen by a veterinary er sooner include: sticky gums that are pale, yellow, blue, purple, temperature rectally >103.5, progressive lethargy with less responsiveness to you, vomiting or diarrhea that includes blood, resting respiratory rate (breaths per minute) >60, swollen abdomen.
Please let me know if I can be of any further assistance to you both today
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