What is eczema?

Eczema is an inflammation of the skin. It is not life-threatening or contagious. However, it typically causes itchiness, discomfort and a dry, scaly rash. The terms eczema and dermatitis are usually used interchangeably. There are several types of eczema, but most people use the term to refer to the most common variety known as atopic dermatitis.

Eczema is a common condition that affects people of all ages and races. It usually begins early in life and often appears periodically throughout your lifetime. In some cases, the condition will improve over time. In other cases, it will remain chronic. Because the disease is intensely itchy, people often have the urge to rub or scratch the affected area. However, this only makes the condition worse.

What are the types and differences of eczema?

There are several different types of eczema. They include:

• Atopic dermatitis. May occur in association with allergies and frequently runs in families with a history of asthma or hay fever. It typically begins in infancy, where it is often related to food allergies, and varies in severity during childhood and adolescence before becoming less troublesome in adulthood. However, exposure to certain allergens or irritants can trigger an outbreak later in life. Stress can exacerbate atopic dermatitis. Some people use the term atopic dermatitis interchangeably with eczema.
  
  
• Contact dermatitis. Results from direct skin contact with various irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Irritants include laundry soap, skin soaps or detergents, and cleaning products. Allergens include rubber, metals such as nickel, jewelry, perfume, cosmetics, hair dye, weeds such as poison ivy, and neomycin, an ingredient often found in topical antibiotic creams. A brief exposure to a small amount of an allergen can cause contact dermatitis. However, it takes a more significant amount of an irritant, and a longer period of exposure, to trigger irritant contact dermatitis.
  
  
• Seborrheic dermatitis. Common in people with oily skin or hair, it involves an overproduction of skin cells and the skin's natural oil, or sebum. It may reoccur depending on the season of the year or whether you are under stress. People who have neurologic conditions such as Parkinson's disease or who are immunocompromised such as in HIV disease also are at risk for this form of eczema. Seborrheic dermatitis is often an inherited condition.
  
  
• Neurodermatitis. Occurs when a tight garment or insect bite irritates the skin, leading to chronic scratching or rubbing and a subsequent rash that is dull red to brown, thickened and slightly scaly. Common locations include ankles, wrists, outer forearms or arms, and the back of the neck.
  
  
• Stasis dermatitis. Occurs on the lower legs when fluid builds up in tissues just beneath the skin, thinning out the skin and interfering with the blood's ability to nourish the skin. Stasis dermatitis is associated with varicose veins and other chronic conditions in the legs.
  
  
• Perioral dermatitis. Often associated with conditions such as rosacea, acne or seborrheic dermatitis of the skin around the mouth or nose. The precise cause is unknown, but exposure to makeup, moisturizers and dental products may be involved.
  
  
• Latex dermatitis. Occurs when the skin comes into contact with latex, a fluid produced by rubber trees and found in gloves, balloons, condoms and other products.
  
  
• Dyshidrotic dermatitis. An intensely itchy, chronic form of eczema that typically appears on the palms, fingers and soles of the feet. The cause of dyshidrotic dermatitis is unknown but may include allergies, exposure to irritants and stress. It often progresses to small, fluid-filled bumps, which peel off after one or two weeks. This leaves cracks in the skin that resolve slowly over time.