Thank you for your question regarding your Havanese girl Chloe who has been panting, shaking and off food tonight. These symptoms are definitely worrying and there are a number of possible causes we need to consider here, including anything from a toxicity, to an infectious gastroenteritis (on the way), to a primary cardio-respiratory issue (just to name a few potential issues here). You are definitely going to need to keep a very close eye on Chloe tonight, and 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.
If you think she could be off food because of nausea, then you may 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
All the best with Chloe and please continue to keep a close eye on her tonight. Hopefully she settles and sleeps soon, but if she is still panting in half an hour, there is no question that you should play it safe and get her seen tonight if you can. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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