After wearing a certain t-shirt for only a couple of hours I noticed my underarms where the seams rubbed were sensitive. These areas have remained extremely sensitive for a week. There is no redness but there might be areas that are slightly raised. The areas are itchy and tender to the touch. I just took an anti-histamine to see if I can get some relief. My question is, could there be something in the threads of the seams that people are commonly allergic to. My skin has also (in the past year) become allergic to the touch of oyster plants (large hives where the plant touches my skin)