I use scent-free products to shower with, and yet I continue to get an itchy back, especially underneath the stretchy parts of my bra in the back.
My dermatologist told me it's my shampoo causing this (though I never mentioned the bra part) and she told me to buy a specific brand of shampoo and conditioner that work terribly on my very thick, coarse hair. I use Fekhai shampoo and conditioner when I can because they bring out the shine in my hair and make styling easier but I swear the conditioner is the culprit.
I'm so upset about this.... any suggestions??
I get reactions down my back as well. I've even gotten them when I've only rinsed off with water in the shower and NOT A THING else. My doctor told me that I can react to water - just plain ol' water. It sounds crazy, but when you think about how many minerals and water pipe build-up is in that water... it could be from nickel, chlorine and who knows what else. Also, here's something interesting that Dr. Scheman told me: even fragrance-free items have fragrance. What they have is MASKING fragrance. If they didn't put the masking fragrance in the products, they wouldn't smell good at all.
Have you tried not getting your hair wet and seeing what your skin does after the shower? I'd try that a few times and compare that to what your skin looks like after washing your hair. Right now, original Prell and Tresemme's Luxurious Moisture conditioner seem to work for me, but that do both have fragrance. Have you tried "Free and Clear" shampoo and conditioner yet? I stay away from it because I'm allergic to the Propylene Glycol in the conditioner and I'm leery of the Pentylene Glycol, but you may be able to use it!
Also, here's a chart which will help you figure out which chemicals are in which products: http://scheman.com/images/Brochures/acag.pdf
Regarding the elastic, I react to elastic too, but it seems to be more from my underwear than my bra. I react to polyester and that could very well be in elastics. There ARE items made with covered elastic, but they're hard to find. I have some undies pinned on my cotton lounge items Pinterest board, but I don't think I've found any bras that are 100% cotton with covered elastic yet. If you do, please pass along the link!
Hope your skin feels better soon!
Sincerely, The Allergista