10 Causes and Triggers of Eczema

Studies show that people with eczema are more likely to have a genetic mutation that causes a deficiency in the protein filaggrin, which is in the skin's outer layer responsible for keeping moisture in but germs and chemicals out. People with filaggrin deficiency develop dry skin where irritants and allergens can enter. In atopic dermatitis, the immune system responds to these substances with inflammation, redness, and itching.

Environmental factors such as dust mites, pet dander, pollen, and certain foods can trigger an eczema flare. These allergens cause the immune system to respond with an inflamed and itchy rash. Climate is also a factor, as eczema flares can increase with both hot and cold extremes. People living in areas with increased pollution may also be more susceptible to these reactions.

Stress can flare-up or worsen the symptoms of eczema. In response to stress, the body releases the hormone cortisol, which suppresses the immune system and increases inflammation throughout the body. People with a chronic inflammatory process like eczema are particularly susceptible to these effects and develop increased skin inflammation with itching, redness, and dryness.

Up to 80% of children with eczema will develop an allergy-related condition like hayfever, food allergies, and asthma. Environmental allergens including mold, pollen, pet dander, and dust mites can also trigger eczema flares. Some people associate certain foods with worsening eczema, such as dairy, eggs, wheat, or soy. Allergy testing may help determine eczema triggers.

Synthetic fibers in clothing often contain chemicals such as flame retardants, dyes, latex and rubber accelerators, chrome, cobalt, and even formaldehyde. All of these compounds can irritate sensitive skin and may cause dermatitis and eczema. Interestingly, recent studies suggest that although coarse wool may worsen eczema, superfine wool may actually improve symptoms.

Skin infections can worsen eczema symptoms. Immunoglobin E (IgE) is an antibody that plays a significant role in allergic reactions. People with eczema have higher-than-average levels of IgE, which renders them hypersensitive to invading bacteria, viruses, and fungi. The body releases histamine to attack invaders, which causes swelling and redness and sets off a chain reaction resulting in eczema.

Swimming in a chlorinated pool can be problematic for people with eczema. Exposure to the high levels of chlorine and other disinfecting chemicals can cause a skin reaction. Swimming in treated water also causes dryness. Interestingly, some people with eczema find chlorinated water eases their symptoms, likely because the chlorine acts as a sanitizer and kills bacteria. After swimming in a public pool, anyone — and especially those with eczema — should shower and moisturize the skin. In some cases, applying moisturizer before swimming can also help reduce eczema flares.

The skin around the eyes is extremely delicate and often more susceptible to eczema. The chemicals in eye makeup may cause irritation and redness, as can other skincare products with perfumes and other additives. Some people may even develop reactions to products they have been using for a long time. Products without harsh chemicals or those made from natural ingredients may be gentler for sensitive skin.

Exposure to household cleaning products can set off eczema, and people prone to reactions should always wear gloves when cleaning. Those with sensitive skin may find that body products like soap also cause irritation, not only due to the ingredients, but also because many soaps remove natural oils and dry the skin. Using natural products that are dye-free and fragrance-free for household cleaning and personal use may reduce skin reactions.

People with eczema who react primarily to environmental factors may find their symptoms are worsened in dry climates. In dry weather or when using indoor heating, keeping the skin well-moisturized is essential. Using a humidifier may also help. On the other hand, very humid weather also causes flares in some people, if sweating exacerbates itching. Sudden changes in weather conditions can also trigger a rash.