Understanding Eczema

Eczema is a common inflammatory skin condition that can make the skin dry, itchy, red, cracked and uncomfortable. For some people it appears as a relatively small patch that comes and goes. For others it can affect large areas of the body and become a persistent problem that interferes with sleep, concentration and everyday life.

Although eczema is visible on the surface, it is not simply a problem of “bad skin.” The protective barrier of the skin, the immune system, genetics, the environment and individual triggers can all play a part.

One of the difficulties with eczema is that no two people experience it in quite the same way. What triggers a flare in one person may have little effect on another. Understanding the individual pattern is therefore an important part of managing the condition.

What is eczema?

The word eczema describes a group of inflammatory skin conditions rather than one single disease. The most common form is atopic dermatitis, and the terms eczema and atopic dermatitis are often used interchangeably.

Healthy skin acts as a protective barrier. It helps keep moisture inside the body while keeping irritants, allergens and microorganisms outside.

In eczema, this barrier does not function as effectively as it should. The skin loses water more easily and becomes dry and vulnerable. Substances that would normally remain outside the skin may penetrate more easily, where they can irritate the skin or stimulate an immune response.

This combination of dryness, barrier weakness and inflammation helps explain many of the characteristic symptoms of eczema.

What does eczema look and feel like?

Eczema can look quite different depending upon the person, the part of the body affected and whether the condition is currently flaring or relatively quiet.

Common symptoms include:

dry or rough skin
intense itching
red, pink, brown, purple or greyish areas of inflammation depending on skin tone
small raised bumps
cracked or fissured skin
scaling or flaking
areas that ooze or form crusts
swelling
thickened or leathery skin after repeated scratching
changes in skin colour after inflammation has settled

For many people, itching is the dominant symptom.

The itch may become particularly noticeable in the evening or at night. Heat, perspiration, dry air and irritating fabrics may make it worse.

Scratching naturally gives temporary relief, but unfortunately it can damage the skin barrier further and increase inflammation.

This creates what is sometimes called the itch-scratch cycle:

itching → scratching → skin damage → inflammation → more itching

Breaking this cycle can be one of the most important parts of bringing eczema under control.

Where does eczema occur?

Eczema can develop almost anywhere on the body, although its distribution often changes with age.

In babies it frequently affects the cheeks, scalp and outer surfaces of the arms and legs.

In children it commonly appears around the elbows, behind the knees, around the wrists and ankles, and sometimes on the hands or face.

Adults may experience eczema on the hands, face, eyelids, neck, elbows, knees or other areas of the body.

Some people have just one troublesome area, such as hand eczema, while others experience widespread dryness and inflammation.

Why does eczema develop?

There is rarely one simple cause.

Eczema is better understood as the result of several interacting factors.

The skin barrier

One of the most important features of atopic eczema is impairment of the outer protective layer of the skin.

The outer layer contains fats, proteins and structural components that help hold skin cells together and prevent excessive water loss.

When this barrier is weakened, the skin dries more easily and becomes more permeable to irritants and allergens.

This is one reason moisturising is such an important part of conventional eczema care. It is not merely cosmetic: moisturisers help compensate for some of the skin's lost barrier function.

Genetics

Eczema often runs in families.

Some people inherit variations in genes involved in the structure and function of the skin barrier. One well-known example involves filaggrin, a protein important for maintaining healthy skin.

Genetics do not determine everything, however. Environmental exposures, immune activity and lifestyle factors influence whether eczema develops and how severely it behaves.

The immune system

Eczema is also associated with an exaggerated inflammatory response within the skin.

The immune system may react strongly to substances or environmental conditions that would cause little difficulty for another person.

This does not mean that someone with eczema has a generally “weak” immune system. Rather, particular aspects of immune regulation and inflammation are behaving differently within the skin.

What can trigger an eczema flare?

A cause and a trigger are not necessarily the same thing. A person may have an underlying tendency toward eczema because of their genetics and skin barrier function, while particular exposures trigger individual flares. Possible triggers include:

Dry skin

When the skin becomes excessively dry, tiny cracks can develop within its protective barrier. This can increase both irritation and itching.

Dry winter air, heating, air conditioning and frequent washing may all contribute.

Soap and detergents

Soap removes oils from the surface of the skin.

Strong cleansers, washing-up liquid, laundry products, disinfectants and household cleaning chemicals can therefore be particularly troublesome for some people with eczema.

Hot water

Long, very hot showers or baths can remove protective oils and leave the skin feeling considerably drier afterwards.

Lukewarm water is usually kinder to eczema-prone skin.

Heat and perspiration

Some people notice that eczema becomes itchy when they are hot or sweating.

Exercise itself does not necessarily cause eczema, but perspiration, heat and friction may aggravate already-sensitive skin.

Clothing

Rough materials such as wool can irritate some people's skin.

Seams, tight clothing and synthetic fabrics that trap perspiration may also contribute.

Soft, breathable fabrics are often more comfortable.

Weather

Cold, dry weather can worsen dryness, while very hot and humid conditions may increase sweating and itching.

For this reason some people notice distinct seasonal patterns in their eczema.

Allergens

Allergy can play a role in some cases, particularly in people with an atopic tendency.

Possible allergens include dust mites, pollen, animals and occasionally foods.

However, eczema should not automatically be assumed to result from a food allergy. Unnecessarily eliminating numerous foods can make a person's diet restrictive without improving the skin.

Suspected allergies are best investigated carefully rather than assumed.

Stress

The connection between emotional stress and eczema is particularly interesting.

Stress does not mean that eczema is “all in the mind.” Eczema is a genuine inflammatory skin disorder.

Nevertheless, the nervous system, immune system and skin continually communicate with one another. Stress can influence inflammatory signalling, itching, sleep and scratching behaviour.

Many people therefore notice that eczema becomes worse during periods of emotional strain.

The relationship can also work in the opposite direction.

Severe itching, visible skin changes and poor sleep can themselves create considerable stress.

The eczema and sleep cycle

Night-time itching can be one of the most exhausting aspects of eczema.

A person becomes warm in bed, begins itching, scratches while half asleep and wakes repeatedly during the night.

Poor sleep then affects energy, concentration, mood and the ability to cope with stress the following day.

The skin, nervous system and sleep cycle can therefore become interconnected.

For someone with persistent eczema, asking “How are you sleeping?” can sometimes be almost as important as asking how the skin looks.

Different forms of eczema

Although atopic dermatitis is the best-known form, several conditions fall under the broader eczema umbrella.

Atopic dermatitis

The most common form.

It frequently begins during childhood and is particularly associated with dry, itchy and inflamed skin. People with atopic dermatitis may also have a personal or family tendency toward asthma, hay fever or allergies.

Contact dermatitis

Contact dermatitis occurs when something touching the skin causes inflammation.

Irritant contact dermatitis can result from repeated exposure to substances such as water, soap, detergents or chemicals.

Allergic contact dermatitis occurs when the immune system reacts to a particular substance. Examples can include nickel, fragrances, preservatives and ingredients in cosmetics.

Hand eczema

The hands are constantly exposed to water, soap, detergents, weather, friction and other irritants.

Hand eczema may therefore become persistent, particularly in people whose work requires frequent hand washing or contact with chemicals.

The skin may become extremely dry, cracked, painful or blistered.

Dyshidrotic eczema

This form produces intensely itchy small blisters, usually on the fingers, palms or soles of the feet.

The blisters may later dry, peel and crack.

Nummular eczema

Nummular or discoid eczema produces round or oval patches of inflamed skin.

The patches can be extremely itchy and sometimes resemble fungal infections, which is one reason an accurate diagnosis can be important.

Seborrhoeic dermatitis

Seborrhoeic dermatitis tends to affect oily areas of the body such as the scalp, eyebrows, sides of the nose and sometimes the chest.

It often produces flaking, scaling and inflammation and is commonly associated with dandruff.

Eczema and infection

Repeated scratching damages the skin surface and can make it easier for microorganisms to enter.

Signs suggesting infection can include:

increasing pain
unusual warmth or swelling
pus
yellow or golden crusting
rapidly worsening redness
fever
suddenly worsening eczema

A significant or rapidly spreading infection needs medical assessment.

People with eczema should also seek prompt medical help if clusters of painful blisters or punched-out sores appear alongside feeling unwell, as this can occasionally indicate a more serious viral infection known as eczema herpeticum.

How is eczema diagnosed?

There is usually no single laboratory test for eczema.

Diagnosis is generally based upon the appearance of the skin, where the rash occurs, its history and the pattern of symptoms.

A doctor or dermatologist may ask about:

when the eczema began
family history
itching
possible irritants
occupational exposures
allergies
skincare products
seasonal changes
previous treatments

Where contact allergy is suspected, patch testing may sometimes be appropriate.

Conventional treatment of eczema

Treatment depends on the severity and type of eczema.

The foundation of care usually involves protecting and moisturising the skin barrier.

Moisturisers and emollients

Regular use of an appropriate moisturiser can reduce dryness and help support the skin's protective barrier.

Many people with eczema need considerably more moisturiser than somebody with normal skin.

Applying it shortly after bathing can help trap water within the skin.

Topical corticosteroids

Topical steroid creams or ointments are commonly prescribed to reduce inflammation during eczema flares.

Different strengths are used depending on the age of the patient, severity of the eczema and area of the body being treated.

When used appropriately under medical guidance, they can be very effective.

Treatment for more severe eczema

When eczema is severe or widespread, dermatologists may consider treatments such as phototherapy, systemic medicines or targeted biologic therapies.

Modern eczema treatment has developed considerably, particularly for people whose condition cannot be adequately controlled with creams alone.

Everyday skin care

Simple measures can make a surprisingly large difference.

Rather than continually trying to “treat” the skin, it can be helpful to think about reducing the number of things the skin has to cope with each day.

This may include using lukewarm rather than very hot water, choosing gentle cleansers, moisturising regularly, avoiding known irritants and wearing comfortable fabrics.

It can also be useful to look at everything that regularly touches the skin: soap, shampoo, laundry detergent, perfume, household cleaners, clothing, bedding and occupational chemicals.

Sometimes a relatively ordinary exposure repeated every day matters more than an exotic explanation.

Looking beyond the surface

Because eczema is a skin condition, it is tempting to look only at what is applied externally.

Skin care is certainly important, but I also like to look at the wider picture.

How is the person's nutrition?

How are they sleeping?

Is their skin constantly exposed to detergents or irritating products?

Are they under unusual stress?

Does the eczema follow a seasonal pattern?

Did anything change shortly before it began?

What makes it noticeably better or worse?

Two people may both receive the diagnosis eczema, yet the circumstances surrounding their condition can be very different.

One person's skin may deteriorate every winter. Another develops eczema primarily on their hands after repeated washing. Another notices a close relationship with emotional stress and sleeplessness.

The diagnosis provides a name for the condition. Understanding the individual person provides the context.

When should you see a doctor?

Eczema should be professionally assessed when the diagnosis is uncertain, symptoms are severe, the skin appears infected, eczema is interfering significantly with sleep or daily life, or ordinary measures are not bringing it under control.

A doctor or dermatologist can also help distinguish eczema from conditions that may look similar, including psoriasis, fungal infections, scabies, rosacea and certain forms of contact dermatitis.

Eczema is rarely just about appearance

The visible rash is only one part of eczema.

The dryness, persistent itching, disturbed sleep and repeated cycles of improvement and relapse can have a substantial effect on someone's quality of life.

For this reason I prefer to look at eczema from both directions: what is happening to the skin itself, and what is happening in the person who owns the skin?

Good skin care remains fundamental. At the same time, nutrition, sleep, stress, environmental exposure and individual triggers may all be worth exploring.

The goal is not simply to find something to put on the rash.

It is to understand the pattern.