Thank you for your patience. Yes - these symptoms in Baylee are definitely a concern. There are a few things that could be causing her symptoms, including the gastrointestinal infection itself, the antibiotics you are giving, a combination of both, or indeed something different entirely. Of course - while she is vomiting, she won't be able to keep any of her antibiotics down either. If Baylee continues to vomit, then she will very quickly become dehydrated, particularly if she can't keep water down. Not eating is also a concern, but not as urgent a worry as her potentially becoming dehydrated quite quickly.
For the next 5 - 6 hours, please withhold Baylee's food until later on today. You can then try her with something bland like cooked, boneless, skinless chicken breast and boiled white rice for a few days. Continue to encourage Baylee to drink. As above - if she can't keep water down, then she will quickly become dehydrated. If this is the case, then you need to get Baylee seen by your local vet or ER vet today. Here they can carry out a full physical exam and run a blood test to try and get a better idea of why she is still vomiting, as well as place an IV catheter to give intravenous fluids.
For now, please keep an eye on her mucus membranes, capillary refill time and respiratory rate tonight as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if she seems to be panting or breathing rapidly throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
For now, you may also want to try her with a little pepcid. The typical dose for this type of situation is 0.25mg per pound of body weight up to twice daily. You can read more about the use of Pepcid in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid
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