There really isn't anything you can do if you've already done testing and meds and still nothing. Just keep shirts on him then to protect his skin a little more. That's what I did for years. Fortunately I found out the trigger.
__________________  The T.U.B. Pack! Toto, Uni, & Bindi
RIP Lord Scrappington Montgomery McLimpybottom aka El Lenguo the Handicapped Ninja 10-12-12 
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