Dermatitis is a general term that describes a skin irritation. Dermatitis is a common condition that has many causes and occurs in many forms. It usually involves itchy, dry skin or a rash on swollen, reddened skin. Or it may cause the skin to blister, ooze, crust or flake off. Examples of this condition are atopic dermatitis (eczema), dandruff and contact dermatitis.
Dermatitis isn't contagious, but it can make you feel uncomfortable and self-conscious. Moisturizing regularly helps control the symptoms. Treatment may also include medicated ointments, creams and shampoos.
- Atopic dermatitis (eczema)
- Contact dermatitis
- Cradle cap
- Diaper rash
- Seborrheic dermatitis
Each type of dermatitis may look a little different and tends to occur on different parts of your body. Signs and symptoms of different types of dermatitis include:
- Atopic dermatitis (eczema). Usually beginning in infancy, this red, itchy rash usually occurs where the skin flexes — inside the elbows, behind the knees and in front of the neck. The rash may leak fluid when scratched and crust over. People with atopic dermatitis may experience improvement and then seasonal flare-ups.
- Contact dermatitis. This red, itchy stinging rash occurs where your skin has come into contact with substances that irritate the skin or cause an allergic reaction. You may develop blisters.
- Seborrheic dermatitis. This condition causes scaly patches, red skin and stubborn dandruff. It usually affects oily areas of the body, such as the face, upper chest and back. Seborrheic dermatitis can be a long-term condition with periods of improvement and then seasonal flare-ups. In infants, this condition is called cradle cap.
- Follicular eczema. With this type, the affected skin thickens and develops bumps in hair follicles. This condition is common in African Americans and in people with dark-brown skin.
Causes of the most common types of dermatitis include:
- Atopic dermatitis (eczema). This type is likely related to dry skin, a gene variation, an immune system dysfunction, a skin infection, exposure to food, airborne, or contact allergens, or a combination of these.
- Contact dermatitis. This type results from contact with something that irritates your skin or causes an allergic reaction. Irritants or allergens include poison ivy, perfumes, jewelry containing nickel, cleaning products, and the preservatives in many creams and lotions.
- Seborrheic dermatitis. This type is caused by a yeast (fungus) that is in the oil secretion on the skin.