Thanks for your reply. There are a few things that can cause what you are seeing on Pixie, such as skin mites, fleas, allergies, bacterial infection, or a condition called Eosinophilic Granuloma Complex. Typically in a situation like this, a thorough exam is performed, skin scrapes are done to look for microscopic mites, sometimes impression smears of the skin are done to look for organisms (i.e. bacteria), and treatment is discussed, and may include antibiotics, cortisone medication, prescription low-allergen food, among other things.
For now, without a specific diagnosis, you can try using an antihistamine called chlorpheniramine to help with the itching. You can purchase 4mg tablets (they are not a prescription product), and give 1/2 tablet every 12 hours. You can also use a pet oatmeal shampoo, and bathe Pixie every 2 days, if needed, to help with the itching. Leave the lather on her for 5-10 minutes before rinsing her off, for the best benefit. Wiping her down with cool or lukewarm water periodically may also help until you can get her into a veterinarian for more specific treatment.
I hope this is helpful. Please let me know if I can assist you and Pixie further. I hope you have a Merry Christmas!