The cause of atopic eczema is not known, but the condition often affects people with a family history of allergies. Many individuals with eczema also have hay fever and/or asthma or have family members with those conditions.
Some factors can trigger a flare-up of eczema or make eczema worse, but they do not cause the condition. Eczema triggers include stress, skin irritants (including soaps, skin care products, or some fabrics), allergens, and climate/environment.