There are two main types of allergy in relation to skin disorders. The first is immediate (or type I) allergy. Here, an immediate reaction occurs when coming into contact with the causative agent. This usually results in hives, but can also lead to swelling wheezing, feeling faint and difficulties in breathing. An example of this form of allergy is peanut or latex allergy.
The second type of allergy is delayed (or type IV) allergy. This is very different as the reaction can take several hours or days to develop and usually causes a rash that is itchy and scaly, much like eczema. The rash can be very red and swollen as well. Common causes of delayed allergy included hair dye, fragrances and preservatives.