I am on my second dog with allergies and it's no fun for either one of us, so I feel your pain. I agree with taking her to a dermatologist, I never had good luck with regular vets treating allergies.
I would have her paws checked for yeast and bacteria, it looks a lot like what we are dealing with. See if your vet can get some Apoquel, it stopped Nikki's itching within a few hours but it's hard to get right now.
If she does have environmental allergies I would have her skin tested and start her on immunotherapy.
Treatment Options for Allergies in Pets | Dermatology for Animals - Part 1
Olivia von Jagenstadt "Nikki" 11/21/2009
Heidi Mouse 02/10/1995 - 02/21/2009