[anonymous]

I knew it (carpeting)! If the dog has a flea allergy, you may not see any signs of fleas. Again one flea bite can wreak havoc.
Work closely with your vet, however…
If the dog’s symptoms continue, please consider consulting a veterinary dermatologist, that was the only thing that helped my dog. Intradermal allergy testing
https://www.preventivevet.com/dogs/canine-atopic-dermatitis-environmental-allergies-in-dogs
Final words about atopic dermatitis in dogs
“It is also very important for any dog with atopic dermatitis to be on a year-round, comprehensive flea control program. Atopic dogs tend to be more sensitive to the bites of fleas, so even occasional fleabites should be prevented. Speak with your veterinarian about a safe and effective flea prevention program for all the pets in your home, and learn more about fleas here”.

“Managing this lifelong condition takes some patience. By using various combinations of therapy, and altering the treatment when needed, your veterinarian can help your atopic dog feel and look their best. And for cases that prove difficult to manage, there are board-certified veterinary dermatology specialists that are available to help. You can search for a specialist in your area on the website for the American College of Veterinary Dermatology”.

The only accurate way to do a food elimination trial is with prescription/therapeutic diet food.

Otherwise, it’s a waste of time.