Why only prednisone make my skin look normal?

My skin is constantly with a flushing/blushing look, it gets white when I press it but it returns after a few seconds. I also have severe Keratosis Pilaris in my lower arms, upper arms and chest. I've done all allergy tests and the only positive results were mold and dust mites, I've tried everything, anti histamines, gluten and lactose free diet but it doesn't matter what I do or where I am my skin is always like this, only prednisone makes my skin looks normal (white and clear). Any help?