You've done an excellent job of meticulously tracking the rash's unpredictable behavior, from its symmetrical spread and stubborn scabbing to the potential triggers you've identified, like the asthma medication and dietary changes. It's particularly telling that the rash seems to flare with wheat consumption, even though your initial blood test was negative—as you've noted, being off wheat before a test can sometimes lead to a false negative, and your description of the other symptoms—joint pain, brain fog, stomach issues—is very compelling. The symmetry of the rash is a crucial detail that often points toward an internal cause, such as an autoimmune response or a systemic reaction, rather than just an external irritant like a plant or mites. I hope your doctor tomorrow takes the time to listen carefully to all of this evidence you've gathered and works with you to find some real answers and effective relief. Don't be discouraged if the rash fluctuates; your detailed history is the most valuable tool you have for getting an accurate diagnosis.

In this case the beer is excellent, but for those who are super sensitive it is likely better to go the full gluten-free beer route. Lakefront Brewery (another sponsor!) has good gluten-free beer made without any gluten ingredients.

Welcome to the forum, @catsrlife! Celiac disease can be diagnosed without committing to a full-blown "gluten challenge" if you get a skin biopsy done during an active outbreak of dermatitis herpetiformis, assuming that is what is causing the rash. There is no other known cause for dermatitis herpetiformis so it is definitive for celiac disease. You would need to find a dermatologist who is familiar with doing the biopsy correctly, however. The samples need to be taken next to the pustules, not on them . . . a mistake many dermatologists make when biopsying for dermatitis herpetiformis. 

You state in an earlier post that you don't have celiac disease. Here in this post you state you will "be doing another test". What will this test be looking for? What kind of celiac disease testing have you had done? If you have used a Entero Labs it sounds like you have had stool testing done for celiac disease which is not widely accepted as a valid celiac disease diagnostic testing method. Have you had blood antibody testing for celiac disease done and do you realize that for antibody testing to be valid you must have been eating generous amounts of gluten for a period of weeks/months? 

No, I've not been diagnosed as celiac.  Despite Entero Labs being relocated to Switzerland/Greece, I'll be doing another test. After eating wheat products in Greece for 4 weeks, there wasn't any reaction.  However, avoiding it here in the states.   Thanks everyone for your responses.