This could be from allergies, or possibly from mites. Without seeing her and doing an exam I can only guess. She should go to your veterinarian's to have skin scrapings and a good head to toe exam, if at all possible. If it is not scabies or demodex(skin mites) then treatment or workup for pollen or food allergies could be pursued by your veterinarian.
Hope this helps. there aren't really any home remedies that will help until you rule some diseases out with your veterinarian.
Dr. Jay Mawhinney
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