oh how horrible. May i suggest a nutritionist. I used her for Layla because she has pancreatitis. However, I was reading her "testimonials" yesterday and realized JUST how many pets she has helped with skin issues- i had no idea!
here is her site
askariel.com
and here are the testimonials (Layla's should be up any day now!)
Canine Liver Disease, Kidney Disease In Dogs
Her name is Susan Davis and I just can't say enough great things about her! On her home page- if you scroll down and look to the left it says - book a consult- be sure to be the $78 dollar one if you do- the more expensive one is with a vet- and it is all done by phone- the BEST 78 dollars i ever spent- she saved Layla.
Also take a look at her products:
Dog Itching--Dog Skin & Coat Problems
but if she can know about your specific problem and what your pup eats- she can be a HUGE help
good luck- it is SO hard to watch them suffer!