Casey Gallagher, MD, is board-certified in dermatology and works as a practicing dermatologist and clinical professor.
Eczema, also known as atopic dermatitis, is an inflammatory skin condition that causes a scaly, inflamed, itchy rash. It can affect people of all ages, but it occurs more frequently in children, especially before age five, than in adults.Although the exact cause of eczema is unknown, it’s believed to be the result of both genetic and environmental factors. Since no tests can diagnose eczema, doctors diagnose it based on a physical exam and whether the symptoms meet specific diagnostic criteria.
Treatments options include:
Different types of eczema can look different and show up in different places, they all share classic signs and symptoms that characterize the condition, which include:
No, eczema is not contagious. You can’t catch it or spread it to someone else. Eczema is believed to be caused by a genetic defect combined with environmental factors, so it isn’t like a skin infection that can be passed from person to person.
The cause of eczema isn't clear, but it's believed to be a combination of genetic and environmental factors. A known mutation interferes with production of a protein called filaggrin, which provides skin cells structure and helps them retain moisture. This allows allergens and irritants to enter cells and trigger inflammation.
There’s no cure, so treatment is aimed at managing symptoms. Eczema is treated with:
Yes, eczema is quite itchy. In fact, an itch may be the first eczema symptom you experience, and scratching that itch may be what causes the rash to erupt on your skin. This is called the acute stage. As your skin heals, though, you enter the subacute stage, which is usually characterized by less itchiness. Your doctor should be able to help you find treatments that quiet the itch.
Eczema and psoriasis both cause red, scaly rashes that come and go. However, eczema favors the crook of elbows and knees, and psoriasis is on the outside of joints. Eczema can make skin look dark and leathery, while psoriasis features silvery scales. Both are immune system-related, but eczema involves the overproduction of T-cells and psoriasis is an autoimmune disease that targets skin cells.
Allergic contact dermatitis is a delayed reaction to touching something you’re allergic to. It causes a raised, red rash and intense itching. Common allergens include latex, metals, and skin-care products. Treatments include topical creams, oral steroids (in severe cases), and avoiding the thing(s) you’re allergic to.
An allergy is basically a mistake of the immune system, which identifies something harmless, such as dust or pollen, as a threat. It then causes your body to try expelling the misidentified substance, such as by sneezing or making your nose run. Skin allergies can cause rashes, hives, and other symptoms. Eczema isn’t an allergic reaction, but it does frequently occur in people with allergies.
Dermatitis is inflammation or irritation of your skin. Several types exist, including:
Dermatitis that’s only on the hands probably indicates your hands are coming into contact with something the rest of your body is not. That’s often soap, skin-care products, dyes, household cleaning products, or certain foods. It may help to wear gloves when in contact with triggers. Your doctor can also help guide your treatment choices.
A patch test is performed to diagnose contact dermatitis. It involves patches (long, narrow strips) with potential allergens applied to small dots. A doctor puts the patch on your skin to see what substances it reacts to. Patches are typically left on for about 48 hours and, because contact dermatitis takes a while to show up, you’ll likely be evaluated a day or two after removal.
Pyun BY. Natural history and risk factors of atopic dermatitis in children. Allergy Asthma Immunol Res. 2015;7(2):101-5. doi:10.4168/aair.2015.7.2.101