and allergy test will only test for the most common things. If it's a reaction to a drug, the allergy test wont show that because they dont test for drugs. Where did you get this? First off eczema, is just extremely dry skin. Psoriasis doesnt come up here and there, it is always there and its usually developed as a child and there is no real cure for it so it's something people live with their whole life. Contact dermatitis is really just a professionally sounds phriase for an allergic reaction to something. Thats also why I asked if the skin was hot to the touch, if so, see a doctor asap, it's infected. Are they large bumps, or small bumps? is the skin around the bumps red? (basically skin is my thing. It is what I do for a living. So if I can see a pic, I can help).