I have to say that I am quite concerned about your lass.
Now hopefully she has pink gums (since pale/white can be a sign of internal bleeding or circulation compromise potentially in the gut) and hasn't eaten something harmful. Still,if she cannot even keep water down and has a hard (likely tense due to pain or even a mass compressing her other abdominal organs) belly, then we need to tread with care.
In fact, if she cannot keep even water down and thus has severe nausea, we'd really want to have her seen urgently to be assessed and have her local vet start injectable anti-nausea medication for her. At the same time, they can determine what is causing the belly hardness you have felt and address it appropriately.
Otherwise, if there is any delay in having Lexie seen, 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. Though again 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.
Since dehydration is a risk here, we need to keep an eye on her hydration. To check this and ensure she’s not becoming dehydrated, there are a few things you can test. Further to checking for gum moisture, you will want to make sure her eyes are not looking sunken 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, a wide range of agents could trigger the GI upset we are seeing (ie gut infections, pancreatitis, etc). But that hard belly and severe nausea just raise some very serious worries at her age. 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, doesn't get more comfortable in her belly or doesn’t respond to the above within a few 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 settle her stomach, and help her recover from this.
Please take care,
If you have any other questions, please ask me – I’ll be happy to respond.
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