Dermatologist says rosacea is a symptom, not a cause. She's treated me for that already, but the treatments make my redness worse, not better. She's run a pile of tests. Discovered a severe B12 deficiency and that's been rectified. Supplementation initially improved the redness ....but now it's back again, despite my B12 levels being too high to measure. I do wonder if my B12 levels are now so high, it's causing the redness -- but my GP doesn't want me to lower the dose, since I have what is likely going to turn out to be permanent nerve damage in one of my feet. (As an aside: wow my feet are far more finicky these days! Because I can actually feel them once again!)
I've been patch-tested for allergies before -- in the distant past. They said I was allergic to oak pollen and mold. And the allergist said then that I was likely to be allergic to a whole lot more, since the patch test is just a patch for most common allergies. So yeah I get your point, but at this stage of the game, I need an allergist not a dermatologist to get to the bottom of things. I just haven't had a lot of time as I'm traveling 90% lately.
Dermatologist and I suspect I am allergic to industrial strength cleaners or pesticides since there seems to be a strong correlation with reactions and being around institutional settings such as hospitals, airplanes, hotels. And also grocery stores that have been recently sprayed with pesticides. I had my first-ever case of all-over hives a couple months ago when visiting a friend in a hospital... that smelled strongly of pesticides. I am super sensitive to the smell of pesticides for some reason -- often I smell and others with me can't smell it. Not sure what is up with that.