My mother suffered from the same thing for years. they tested and tested ( gave away her cats, changed every product) and eventually told her it was all in her mind. Turned out to be Celiac Sprue disease (which they said they had tested her for previously) but by then all her celia had been destroyed in her gut and she could not digest any food. But it all started with itching. She would have had to use a feeding tube or something but unfortunately it was discovered she had lung cancer too and that got her first. She never did get to have her last meal she so craved. A Rueben sandwich and a beer. Prayers to you, anon.