What you describe sounds like environmental allergies, food would have little impact, if any, on this condition.
I would continue to work with your veterinarian, however, for best results, I would go to a specialist, a veterinary dermatologist.
Have you tried the search engine here? This subject comes up frequently.
Example: /forums/topic/irritated-skin-food-allergy/
/forums/topic/dog-chewing-nails-till-they-bleed/
“Food allergies are rare. Food sensitivities tend to result in GI disturbances such as vomiting and diarrhea. Environmental allergies tend to show up as pruritus, ear infections and such”.
“You could try a limited ingredient grain free food. My dog does well on Nutrisca Salmon and Chickpea. Wipe down her feet with water and gently dry when she comes in from outdoors”.
“Bathe her using a gentle shampoo, I use Malaseb (see chewy dot com).
I tried all kinds of things times 1 year (including going back and forth to the veterinarian), but, did not get results till I took her to a dermatologist for testing. Allergen specific immunotherapy worked in her case”.
Unfortunately, steroids and such are often necessary (for brief periods) to stop the suffering and prevent infection.
Allergen specific immunotherapy is the most natural treatment.
Also, I have heard that some dogs do well on apoquel, you may want to consider staying with that, talk to your vet.
