Now we do need to be careful with Luna. Vomiting and diarrhea can quickly lead to dehydration and weakness in kittens, so we want to be proactive here. With this in mind, I'd first note that if she was vomiting first, then that nausea would have been why she vomited her wormer. So, we'd really want to be addressing her nausea before going forward. To do so, 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 a OTC pet safe antacid. [ie Pepcid (More Info/Dose @http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid), 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 food to allow absorption. Of course, do double check with your vet if she has a known health issues or is on any medications you haven't mentioned. Though if you give this and she cannot keep it down due to nausea that is usually a red flag that we need to bypass her mouth with injectable anti-vomiting medication from her vet.
If you she seems weak and lethargic, we can try boosting her blood sugar by rubbing a sugary syrup (ie glucose syrup, honey, karo syrup, pancake syrup, or even non-grape jam) onto the gums. This will get some sugar into your wee one and hopefully perk her up for us. Afterwards, you can consider starting her on an easily digestible diet like boiled chicken, boiled white fish, 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. 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/diarrhea. Fiber (ie canned pumpkin) and OTC probiotics (ie Benebac, Fortiflora) can be added to these meals to firm those loose stools quicker and support digestion. Or if she is very loose, you could also use Kaolin/Kaopectate (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/kaolin-and-pectin-kapectolin-k-p)). This is available OTC at most pharmacies (of course avoid Imodium, Pepto Bismol or salicylic acid/aspirin containing products as those aren't cat friendly). Otherwise, Propectalin, Canikur, Fast Balance, and Protexin Pro-Fiber (all OTC at vets, pet stores, and even Amazon) would be another option. All will slow diarrhea and those last ones have the added bonus of probiotics added in. So, these can be used as a short-term means of soothing her upset GI.
Since dehydration is a risk for little kittens when vomiting, we need to keep an eye on her hydration. To check that she isn't dehydrated, there are a few things you can test. Further to checking for gum moisture, do make sure she doesn’t have sunken eyes and that she doesn’t have a "skin tent" when you lift the skin. To see how to check these parameters for dehydration, you can find a good video HERE (http://www.ehow.com/video_12232503_dog-dehydrated.html). If you are seeing any signs of dehydration already, then that would be our cue to have her seen before this becomes an additional issue for her (especially as it is often dehydration that makes them feel unwell).
Overall, Luna's signs do raise a few concerns. It may be the worms alone that have unsettled her and if the wormer had time to absorb it may address the root cause. OF course, we also have to be wary of bacterial or viral gut infections and foreign bodies at her age. So, we’d want to start supportive care to settle her stomach. If she cannot keep that or water down at any point, 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-vomiting medication, fluids, +/- antibiotics to get her back feeling like herself.
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