Thank you for your patience. There are quite a number of things that could be going on here with your girl from an allergic reaction to something, to external parasites, or even an internal issues which is also causing a secondary skin issue. You are definitely going to need to continue to keep a close eye on your girl, and if this rash doesn't improve much in the next day or two, you will definitely need to follow up with a local vet. For now, as this is quite possibly an allergy, give your girl a wash and shampoo using a canine oatmeal shampoo (or similar) from your local pet store. Be sure to rinse this off properly. This will hopefully help to soothe your girl's issue. You can also try a little Benadryl - the typical dose is 1mg per pound of body weight up to twice daily. You can read more about the use of Benadryl in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/diphenhydramine-benadryl .
It is also very important that you make sure your girl is up to date with external parasite treatments - particularly flea and mite control. You will need to use a reliable product of an appropriate size for her weight and I would recommend Advantage Multi for this (available from your local vet). Be sure to treat all of the animals in your home at the same time, and wash all of their bedding to ensure all flea larvae are killed as well.
In case there is something else going on here, please also 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.
As above, if her issue doesn't settle within the next day or so, or if she is particularly distressed now, then you will definitely need to follow up with your local vet tomorrow or Thursday. 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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