6 Main Types of Eczema You Might Not Know

Here's what scientists think about the possible causes of this common skin condition.

1. Atopic dermatitis

The most common type of eczema is atopic eczema, also known as atopic dermatitis. The dry, red, scaly skin frequently appears on the outer surfaces of joints such as the elbows and knees. Cracks behind the ears, a rash on your arms, legs, or cheeks (often caused by scratching the itch), or even open, leaking sores are all possible symptoms.

Chemicals, stress, temperature changes, and allergens touching the skin can all trigger atopic eczema. The skin barrier is not maintained in people with atopic dermatitis. The skin is not retaining the necessary fats, resulting in microscopic cracks. The mortar between the bricks appears to be missing.

Atopic dermatitis runs in families, and many people who have it also have asthma and hay fever.

2. Contact dermatitis

Contact dermatitis is similar to atopic dermatitis in that it occurs when the skin comes into contact with irritating substances such as nickel or a specific chemical. It can cause redness, burning, swelling, and blisters that "weep" before hardening into a crust. Contact dermatitis symptoms typically appear where the skin came into contact with the irritant, which is frequently the hands. Many people suffer from both contact eczema and atopic eczema.

Contact dermatitis has several subtypes, the most common of which are irritant contact dermatitis and allergic contact dermatitis.

Irritant contact dermatitis is caused by substances that, in high enough concentrations, would irritate anyone, such as bleach, acid, or poison ivy. Contact dermatitis caused by allergies is a real allergy. The immune system is reacting as if the situation is dangerous when it is not.

Fragrances, hair dyes, detergents, tobacco smoke, paint, wool, rubber, leather, certain skincare products (including soap), and allergens are all potential irritants (like pet dander).

3. Dyshidrotic eczema

Dyshidrotic eczema is distinguished by small, itchy blisters that appear on the hands and feet and are extremely painful. Irritating substances, once again, can cause a flare. Symptoms can also appear during times of stress, when temperatures rise, or when your hands remain wet for an extended period of time.

While all types of eczema can be severe, dyshidrotic eczema can be crippling if blisters on your feet make it difficult to walk or hand blisters interfere with daily tasks or work.

4. Nummular (or discoid) eczema

Nummular or discoid eczema differs from other types in that it is always round and often described as "coin-shaped." The term "nummular" simply refers to the shape of the lesion. It's a circular spot.

It also itches frequently and can be more difficult to treat than other types of eczema. Insect bites (which break the skin) and winter dryness are common triggers.

5. Seborrheic dermatitis

When it appears on your scalp, seborrheic eczema is more commonly known as dandruff (also called "cradle cap" in babies). However, it can also appear on other parts of the body with sebaceous (oil-producing) glands, such as your nose and upper back. Hormones and yeast can make the condition worse.

Seborrheic dermatitis can cause the skin to become red, but it can also result in greasy, swollen patches. Fine flakes or thicker white or yellow flakes that crust may appear.

Unless severe, it is usually not as bothersome as other types of eczema. Sometimes anti-dandruff shampoo is sufficient to control it, but stronger prescription shampoos are also available.

6. Stasis dermatitis

Stasis dermatitis is unlike other types of eczema in that it is a symptom of deeper problems-literally. In fact, stasis dermatitis is a sign of circulatory and blood-flow issues. Aside from red, itchy, flaky skin, ankles may swell and blisters may turn into ulcers.

Stasis dermatitis can be a warning sign. You can use creams, but in the end, you should see a cardiologist or a vascular doctor.

In some cases, surgery may be required to repair the damaged veins. Swelling can be reduced by wearing support stockings and elevating the legs.