Now I have to say that I am quite concerned for your lass.
To see all these signs together raises concerns of her GI signs being related to the allergic reaction (especially if the allergen was eaten) or that we have another issue brewing (ie gut infection, pancreatitis, dietary indiscretion, etc). And I would also note that if you are bathing her feet and she is then chewing them, then we may also have a gut upset related to the cleanser.
With all this in mind, we do need to approach this in a step-by-step manner. To start, she cannot be allowed to chew her feet. This may mean covering them with socks or using an e-collar for the short term.
If she settles, then we likely have our culprit. Otherwise, if she remains nauseous, we can try a bit of stomach supportive care. 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), or Zantac (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/ranitidine-hcl-zantac). 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, if we can settle her stomach but her feet are still irritating her, then we’d need to address that as well. You can ring her vet about dispensing further treatment or at least consider continuing an oral antihsitamine. 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 that allergic irritation. We like to keep the dose low, as it can cause drowsiness (just like people). And of course, this medication shouldn't be used if your wee one has any pre-existing conditions, is still nauseous (since this could upset the stomach further) or is on any other medication without speaking to your vet first.
Overall, her signs do raise a few concerns of this being directly or indirectly related to her recent skin issues. Therefore, we’d want to start the above just now to see if we can soothe her stomach and then her skin. If we can do so, we are happy. Though if these signs linger, we’d want a recheck with her vet to make sure there is nothing else present and to get her onto further treatments for each issue to nip this in the bud for her.
Please take care,
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