Two things come to mind...a food allergy or insect bites...not necessarily from fleas.
First topic...food allergy. Dogs can develop allergies to foods that they have been eating for years, so don't dismiss this possibility. Ingredients like corn and beef are the top problems associated with food allergies.
Insect bites can cause some major problems...just one bite and the dog can break out severely :(
You can discuss these options with your vet and you can offer your baby some benedryl to help with the itching. 1-2mg per pound of body weight is the correct dosage.
If you would like to do a food switch, to see if that helps (could take around a month before you notice a change) I would suggest you go with a food like Eagle Pack Holistic. You can read more about Eagle Pack here:
www.eaglepack.com
You can also apply neosporin to the affected area to see if that helps too. Also, consider using an oatmeal shampoo on your girl as she may be developing a reaction to the flea and tick shampoo. Labs normally have very sensitive skin. If the condition worsens, please see your vet :)
Good luck and hope she feels better soon :)
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