Hi, Thanks for writing in. Since your condition produces the same skin reaction at both the underarm and groin areas, it is reasonable to assume that both problems are caused by the same disorder. Consequently, something simple like an allergic reaction to an underarm deodorant product is not likely to be the cause. However, the underarms and groin are areas of the body that rarely become dry so I suggest you dry yourself properly after shower. If it remains to stay sticky even after drying with redness in the areas then the possibility of a fungal infection needs to be considered. Hope this helps