Thank you for your patience regarding your girl Lizzie. As you can probably appreciate, in an older dog, there are quite a few possible causes for this vomiting and lethargy including anything from simple gastroenteritis, to a foreign body in her intestinal tract, to pancreatitis, an endocrine problem or even an internal organ issue (given her age). Whatever the case, you are going to have to continue to keep a close eye on your girl over the next few hours. If the vomiting continues and she can't keep food or water down, then the most immediate concern would be that she could quickly become dehydrated. If she won't drink or can't keep water down, then you really are best to have her seen by your local vet or ER vet now if you can. Here they can check her over and start her on some 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/drug-library/famotidine-pepcid/page1.aspx .
As above, if she continues vomiting, develops any other symptoms or can't keep water down, then you really should get Lizzie seen by your local vet or ER vet straight away. I hope all of the above makes sense? Please let me know if you have any other questions. My goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back. I am happy to address follow-up questions. Thank you for your business and I hope to work with you again soon!
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