[anonymous]

“Allergies can be broken down into inhalant, contact, or food allergy origins. Flea allergies, grass allergies, and environmental toxin induced allergies are the most common causes of skin conditions in Cairns. Allergies can be chronic or seasonal. They can be minor or severe in occurrence. They tend to become worse with age. Treatment is much better than in bygone days. Environmental controls, antihistamine treatment, and desensitization injections have made huge strides in the last few years”.
“Glucocorticoids should be used only as a last resort due to serious side effects. Diagnosis and treatment of chronic or severe cases by a Board Licensed Veterinary Dermatologist is recommended”.
(excerpt from:) http://cairnterrier.org/index.php/Static/health
This was copied from a site regarding Cairn Terriers, however, the information applies to all dogs (imo)
Also, you may want to use the search engine here to search “allergies”
Example: Have you consulted a veterinary dermatologist? If the allergies are environmental, changing the diet will have very little to do with alleviating the symptoms.
Environmental allergies tend to wax and wane, without getting Intra dermal skin testing done by a specialist (veterinary dermatologist) it’s pretty much impossible to tell what the allergens are, what is working, or not.

And:
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.