Eczema Causes and Triggers

What causes eczema?

We don’t know what exactly causes eczema. However, for most types of eczema, researchers believe a combination of genes and triggers are involved.

People with eczema tend to have an over-reactive immune system that when triggered by a substance outside or inside the body, responds by producing inflammation. It is this inflammation that causes the red, itchy and painful skin symptoms common to most types of eczema.

Research also shows that some people with eczema have a mutation of the gene responsible for creating filaggrin. Filaggrin is a protein that helps our bodies maintain a healthy protective barrier on the very top layer of the skin. Without enough filaggrin to build a strong skin barrier, moisture can escape and bacteria, viruses and more can enter. This is why many people with eczema have very dry and infection-prone skin.

Eczema triggers

Working to keep your symptoms under control is important to staying healthy and comfortable while living with eczema. When trying to identify potential triggers, keep in mind that an eczema flare can appear some time after exposure. This lag time can make some triggers challenging to detect.

Eczema affects everyone differently. One person’s triggers may not be the same as another’s. You might experience eczema symptoms at certain times of the year or on different areas of your body.

Common triggers include: 

  • Dry skin. When your skin gets too dry, it can easily become brittle, scaly, rough or tight, which can lead to an eczema flare-up.
    Learn more about the importance of moisturizing skin to manage eczema flares.
  • Irritants. Everyday products and even natural substances can cause your skin to burn and itch, or become dry and red. These can include products that you use on your body or in your home — hand and dish soap, laundry detergent, shampoo, bubble bath and body wash, or surface cleaners and disinfectants. Even some natural liquids, like the juice from fresh fruit, vegetables or meats, can irritate your skin when you touch them.
    Common irritants include: 
    • metals (especially nickel)
    • cigarette smoke
    • soaps and household cleansers
    • fragrances
    • certain fabrics like wool and polyester
    • antibacterial ointment like neomycin and bacitracin
    • formaldehyde, which is found in household disinfectants, some vaccines, glues and adhesives
    • isothiazolinone, an antibacterial that is found in personal care products like baby wipes
    • cocamidopropyl betaine, which is used to thicken shampoos and lotions
    • paraphenylene-diamine, which is used in leather dyes and temporary tattoos, among others

Read how one mom helped her son’s eczema by changing her laundry routine.

  • Stress. Emotional stress can be an eczema trigger, but it’s not exactly known why. Some people’s eczema symptoms get worse when they’re feeling “stressed.” Others may become stressed, just knowing they have eczema, and this can make their skin flare up.

Learn more about how stress and eczema are related.