Eczema

What causes eczema? 

While it’s not entirely understood what causes eczema, there seems to be a complex interplay between genetic, immunologic, and environmental factors. 

 Let’s start with some background: The outermost layer of your skin is called the epidermis, and it acts as a physical barrier against environmental insults and water loss. In eczema, there are two primary problems. First, there is a genetic “barrier defect” (eg, a compromised, less-protective epidermis). Second, the skin’s own immune system responds excessively to environmental allergens and irritants.

 The barrier problem results in small breaks in the skin, allowing irritants to permeate, and causing excessive dryness from loss of moisture. This leads to itchiness and the urge to scratch. Scratching triggers the hyperreactive immune response, which in turn causes more itching, leading to a vicious cycle that provokes the characteristic skin lesions (rash) we see in eczema.

 Is eczema linked to any other diseases? 

People with eczema are more likely to also have asthma and environmental allergies (allergic rhinitis), and often have a family history of these conditions as well. 

 Can eczema be caused by food allergies? 

Rarely, eczema flares may be related to a food sensitivity, but in the great majority of cases, no meaningful food allergy or trigger exists. Testing for food and environmental allergies is not recommended. 

Which environmental factors commonly trigger eczema? 

People with eczema tend to be sensitive to a variety of environmental triggers. Avoid bubble baths, fabric softener sheets, harsh soaps, and detergents. Wool and other types of scratchy clothing are other common triggers. Exposure to cigarette smoke should also be avoided.

 In some people, dryness and itchiness may be worse in the winter months when the humidity is low. Others are easily irritated by sweat, and struggle more during the summer months.

 Try to keep the temperature and humidity in your home fairly constant. A vaporizer or humidifier in the bedroom can be helpful in the winter. An air conditioning unit may be necessary in the summer. When using these devices, it’s important to clean them well and frequently, as they can be sources of mold, which can also irritate the skin. 

 Is eczema contagious? 

No, it’s not. While the exact cause is unknown, it’s thought to be an interplay between genes and environmental triggers.