First, I am glad to hear that is normal for her, but we do need to keep an eye on that belly. Now based on the signs we are seeing, we do have a few concerns. Common causes we need to consider include bacterial or viral gastroenteritis, pancreatitis, parasites/protozoa infections, general dietary indiscretions (like cookies not intended for dogs), and ingestion of harmful items (hopefully less likely here). And I have to say that if she is itchy too, then we could have a mild allergic reaction causing all her signs.
With this all in mind, since she can keep water down, we can try some home supportive care to see if we can settle her stomach. To start, if she hasn’t just vomited (since otherwise we’d need to rest her stomach for a few hours first), then you can consider treating her with an antacid. Common pet safe OTC ones we can use include Pepcid (More Info/Dose @http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid), Zantac (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/ranitidine-hcl-zantac), or Tagamet (More Info/Dose Here @ http://www.petplace.com/article/drug-library/library/over-the-counter/cimetidine-hcl-tagamet). Whichever you choose, we’d give this 20 minutes before offering food to allow absorption. Of course, do check with her vet before use if she has any known health issues or is on any medications you didn’t mention. As well, if you try this and find her nausea too severe to keep it down, then that is usually a red flag that we need her vet to bypass her mouth with injectable anti-vomiting medication.
Once that has had time to absorb and she is steadier on her stomach, you can consider starting her on a light/easily digestible diet. Start with a small volume (a spoonful). Examples you can use are cooked white rice with boiled chicken, boiled white fish, cottage cheese, scrambled eggs, or meat baby food (as long as its garlic/onion free). There are also OTC vet diets that can be used (ie Hill’s I/D or Royal Canin’s sensitivity) too. When you offer that spoonful, give her 30 minutes to settle. If she keeps the food down, you can give a bit more and so on. As her stomach stabilizes, you can offer more. The aim of these diets is that they will be better tolerated/absorbed by the compromised gut. Therefore, it should get more nutrients in and result in less GI upset. As long as improvement is being seen, I usually advise that the diet be continued until her signs are settled, and that they are then slowly weaned back to their normal diet.
Finally, once her stomach is settled and if she is still itchy, we can consider giving her a low dose of an antihistamine. Most commonly we use Benadryl/Diphenhydramine (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/diphenhydramine-benadryl). A low dose (ie. 0.5-2 mg per pound of their body weight twice daily) can just be enough to reduce any allergic irritation. We like to keep the dose low, as it can cause drowsiness (just like people). As well, since these can cause nausea if their stomachs are upset, we need to use the above to settle that first before using these. A
Overall, a wide range of agents could trigger the GI upset we are seeing, but with these signs and the itchiness it is quite possible this is related to her being fed cookies that that haven't agreed with her. Therefore, in her case, we’d want to start supportive care to settle her stomach. If she cannot keep that or water down, appears dehydrated already, or doesn’t respond to the above within 12-24 hours; then we'd want to get her vet involved. They can assess her hydration, rule out fever, make sure there is nothing in her stomach that shouldn't be there or any sinister viruses present. Depending on their findings, her vet can treat her with injectable anti-nausea medication, anti-inflammatories to counter her itching +/- antibiotics to settle her stomach, and get her back feeling like herself.
Please take care,
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