- dark colored patches
- rough, scaly, or leathery patches
- crusting and oozing
Eczema is not contagious, which means that a person cannot catch it or pass it onto another person.
In this article, we look at seven different types of eczema, their symptoms, and what causes them. We also cover diagnosis, treatment, and how to prevent flare-ups.
1. Atopic dermatitis
Atopic dermatitis is the most common form of eczema.
Atopic dermatitis, or atopic eczema, is the most common type of eczema.
Symptoms often present in childhood and can range from mild to severe. A child is more likely to develop atopic dermatitis if one of their parents has had it.
Some children may grow out of atopic dermatitis.
Atopic dermatitis tends to cause patches of dry skin that can become itchy, red, and inflamed. These patches often appear in the creases of the elbows and knees and on the face, neck, and wrists.
Scratching the patches can worsen the itching and make the skin ooze clear fluid. Over time, repeated scratching or rubbing can cause the patch of skin to thicken. This is known as lichen simplex chronicus (LSC).
People with atopic dermatitis usually experience flare-ups, where the eczema gets worse for a time. Triggers of flare-ups include:
- low humidity, cold weather, and extreme changes in temperature
- irritants, such as detergents, soaps, perfumes, and fragrances
- dust mites
- animal hair and saliva
- skin infections, including scabies
- certain fabrics, such as wool and synthetics
- hormonal changes, often before periods or during pregnancy
- food allergies
2. Contact dermatitis
Contact dermatitis is a reaction of the skin to certain substances.
Image credit: Digitalgadget, (2007, July 22).
Some people experience a skin reaction when they come into contact with certain substances. This is known as contact dermatitis.
Symptoms of contact dermatitis can include:
- dry, red, and itchy skin that may feel as though it is burning
- hives, a type of rash that consists of small, red bumps
A person with atopic dermatitis has an increased risk of contact dermatitis.
There are two types of contact dermatitis:
Irritant contact dermatitis
Irritant contact dermatitis can result from repeated exposure to a substance that irritates the skin, such as:
- acids and alkalis
- fabric softeners
- harsh detergents
- hair dyes
- weed killers
- some shampoos
People who regularly use or work with these substances have a higher risk of developing contact dermatitis.
Allergic contact dermatitis
Allergic contact dermatitis occurs when a person's immune system reacts to a particular substance, known as an allergen.
A person might not react to an allergen the first time they come into contact with it. However, once they develop an allergy, they will usually have it for life.
Possible allergens include:
- glues and adhesives
- latex and rubber
- some medications, such as topical and oral antibiotics
- fabrics and clothing dyes
- some plants, including poison ivy, poison oak, and sumac
- ingredients in some makeup, nail polishes, creams, hair dyes, and other cosmetics
- certain metals, such as nickel and cobalt
3. Dyshidrotic eczema
Dyshidrotic eczema may cause small blisters.
Dyshidrotic eczema, or pompholyx eczema, typically appears in adults under 40 years of age. It usually occurs on the hands and feet and has characteristic symptoms, including intense itching and the appearance of small blisters.
In some cases, the blisters can become large and watery. The blisters may become infected too, which can lead to pain and swelling. They may also ooze pus.
Blisters typically clear up within a few weeks. Following this, the skin often becomes dry and cracked, which may lead to painful skin fissures.
It is unclear what causes dyshidrotic eczema. However, it is more common in people who have:
- hay fever
- atopic dermatitis or a family history of atopic dermatitis
- fungal skin infections
People who work with certain chemicals or have their hands immersed in water throughout the day are also at greater risk of developing dyshidrotic eczema.
Other triggers include emotional stress and changes in the weather.
Dyshidrotic eczema may be a form of contact dermatitis. People with dyshidrotic eczema also tend to experience flare-ups from time to time.
4. Discoid eczema
Discoid eczema causes characteristic disc-shaped patches.
Discoid eczema, or nummular eczema, is recognizable due to the disc-shaped patches of itchy, red, cracked, and swollen skin that it causes.
The discs typically appear on the lower legs, torso, and forearms. Sometimes, the center of the disc clears up, leaving a ring of red skin.
Discoid eczema can occur in people of any age, including children.
As with other types of eczema, the causes of discoid eczema are not fully understood. However, known triggers and risk factors include:
- dry skin
- skin injuries, such as friction or burns
- insect bites
- poor blood flow
- cold climate
- bacterial skin infections
- certain medications
- sensitivity to metals and formaldehyde
- atopic dermatitis
5. Seborrheic dermatitis
Seborrheic dermatitis can affect the scalp.
Seborrheic dermatitis is a common condition that causes a red, itchy, and flaky rash. The rash can appear swollen or raised, and a yellowish or white crust may form on its surface.
Seborrheic dermatitis develops in areas where the skin is oily, such as the:
- upper chest and back
Seborrheic dermatitis can affect people of any age. Cradle cap is a type of seborrheic dermatitis that can occur on the scalp of babies, but this usually disappears after a few months.
In adults, seborrheic dermatitis has no cure and people will continue to experience flare-ups from time to time. It is common in people between 30 and 60 years of age.
Certain medical conditions can increase the risk of seborrheic dermatitis. These include:
- Parkinson's disease
- acne, rosacea, and psoriasis
- alcohol use disorder (AUD)
- recovering from stroke or heart attack
- eating disorders
Certain medications, including interferon, lithium, and psoralen, can also increase the risk of seborrheic dermatitis.
6. Varicose eczema
Varicose eczema often occurs alongside varicose veins.
Getting older and being less active can weaken the veins in a person's legs. This can lead to both varicose veins and varicose eczema.
Varicose eczema typically affects the lower legs and symptoms can include:
- hot, itchy spots or blisters
- dry, scaly skin
- weepy, crusty patches
- cracked skin
The skin on the lower leg may become fragile, so it is important to avoid scratching and picking at the spots and blisters.
7. Asteatotic eczema
Asteatotic eczema, also called xerotic eczema and eczema craquelé, generally only affects people over 60 years of age. This may be due to the skin becoming drier as a person ages.
Asteatotic eczema typically occurs on the lower legs, but it can also appear on other parts of the body. Symptoms include:
- cracked, dry skin with a characteristic appearance that people describe as crazy paving
- pink or red cracks or grooves
- itching and soreness
As with other types of eczema, the causes of asteatotic eczema are unknown, but triggers can include:
- dry, cold weather
- hot baths
- soaps and other detergents
- excessive cleaning or scrubbing of the skin
- rough towel drying
Diagnosis and when to see a doctor
A skin patch allergy test may help to diagnose the cause of eczema.
People who experience symptoms of eczema should see a doctor or dermatologist. Eczema can indicate a new allergy, so it is important to determine what is causing the reaction.
There is no specific test to diagnose most types of eczema. The doctor will want to know the individual's personal and family medical history. They will also ask about recent exposures to potential allergens and irritants. It is essential that people let the doctor know if they have hay fever or asthma.
The doctor may also ask about:
- sleep patterns
- stress factors
- any previous treatments for skin conditions
- any use of steroids
A physical examination of the rash will help the doctor to diagnose which type of eczema it is.
The doctor may also perform a patch test, which involves pricking a person's skin with a needle that contains potential irritants and allergens. A patch test can determine whether or not someone has contact dermatitis.
There is no cure for eczema, so treatment involves managing the symptoms and trying to prevent further flare-ups.
Some treatment options for eczema include:
- moisturizers or emollients to keep the skin hydrated and reduce itching and cracking
- steroid creams and ointments to reduce swelling, redness, and soreness
- antihistamines to reduce itching, especially at night
- topical calcineurin inhibitors to help reduce inflammation
- phototherapy, which uses ultraviolet (UV) light to fight inflammation
- antibiotics to treat bacterial skin infections
Some general tips that may help to prevent eczema flare-ups include:
- using gentle soaps and detergents
- avoiding fragrances or perfumes
- using cooler water for showers and baths
- drying or toweling the skin gently after washing
- avoiding scratching or rubbing patches of eczema, as damaging the skin can make eczema worse and increase the chance of infection
- moisturizing thoroughly and regularly with gentle, oil-rich products
- applying non-cosmetic moisturizers after showers and baths to keep the skin hydrated
- wearing clothing made of natural fibers and avoiding tight clothing
People with eczema will also benefit from working with their doctor or dermatologist to identify what triggers or worsens their symptoms. Avoiding specific triggers or allergens can help to prevent or minimize flare-ups.