Everything you need to know about eczema and how to treat it.
By Annie Hayes
Eczema is the term used to describe a series of skin conditions that cause the skin to become itchy, dry and cracked. It’s often called atopic dermatitis, which is the most common form of eczema – there are seven in total, including contact dermatitis, dyshidrotic eczema, neurodermatitis, nummular eczema, seborrheic dermatitis, and stasis dermatitis.
While each type of eczema has its own specific symptoms and triggers, all tend to flare up, disappear, and then flare up again, which can be frustrating across the long-term. Dr Roger Henderson explains what eczema is, what it looks like, the different causes of eczema, and how to treat it:
What is eczema?
Eczema is the most common type of dermatitis, a general term that describes a skin irritation and inflammation. Eczema causes the skin to become dry and cracked, but the main symptom is a very itchy rash, which can make it very difficult to concentrate and sleep well.
Eczema is not contagious, and the exact cause is unknown. However, it occurs due to a combination of genes and environmental triggers.
For people with lighter skin tones, the affected skin will often turn red. In darker skin tones, the skin will turn brown, purple, grey or ashen. Eczema is not contagious, and the exact cause is unknown. However, it occurs due to a combination of genes and environmental triggers.
Eczema is divided into a small number of subgroups based on the potential causes of the condition. It’s possible to have more than one type of eczema at the same time.
✅ Atopic eczema
Atopic dermatitis is the most common form of eczema. It’s a long-term (chronic) skin condition for most people, although it can improve over time. This is particularly true among children, with around two thirds growing out of it as they get older. Atopic eczema is commonly seen in people have hay fever and/or asthma. It occurs when your skin’s barrier is weakened, leaving you more susceptible to irritants in the environment.
✅ Contact dermatitis
Contact dermatitis occurs when you touch a substance that irritates your skin or causes an allergic reaction. There are two kinds: allergic contact dermatitisis, which involves an immune system reaction to an irritant – for example, latex – and irritant contact dermatitis, which develops when a chemical directly touches your skin.
✅ Dyshidrotic eczema
Dyshidrotic eczema – also called pompholyx or foot-and-hand eczema – causes blisters to form on the palms of hands, soles of your feet and edges of your fingers and toes. Common in people who have another form of eczema, it can be caused by allergies, exposure to certain metals, such as nickel or cobalt, stress, and humid weather. People who frequently get their hands wet, like hairdressers, may also be susceptible to dyshidrotic eczema.
Neurodermatitis is similar to atopic dermatitis, except it’s usually confined to one or two patches of skin. It can develop anywhere you can reach to scratch, but is most common on the feet, ankles, neck, scalp, hands, wrists, elbows and shoulders. The intense itching associated with neurodermatitis can be caused by tight clothing, and certain conditions can increase the likelihood of developing it – such as psoriasis and anxiety disorders.
✅ Nummular eczema
Nummular eczema causes coin-shaped patches to develop on the skin. They’re often itchy, and sometimes ooze fluid. They may also be dry and crusty. Causes include trauma to the skin – from insect bites, scratches or chemical burns – and dry, sensitive skin. It can also develop as a reaction to other types of eczema and their triggers.
✅ Seborrhoeic dermatitis
Seborrhoeic eczema appears in areas where there are many oil-producing glands. In infants, it’s common in the nappy area and the scalp. In adults, it also appears on the scalp and eyebrows, and in the skin creases between the nose and sides of the mouth. It can be caused by an increased sensitivity to Malassezia yeast, which lives on the skin’s surface.
✅ Stasis dermatitis
Stasis dermatitis occurs due to poor circulation in the lower legs. It’s caused by fluid leaking out of weakened veins, which causes water and blood cells to pool around the ankles. People with stasis dermatitis often have varicose veins and develop open sores.
When an internal or external allergen fires up the immune system, it produces inflammation that causes the symptoms common to most types of eczema – including:
Itching is the main symptom of eczema. ‘Without it a rash is not due to eczema, unless the itch has been improved by treatment,’ says Dr Henderson. ‘Itching is a common feature of many other skin conditions – as well as being a symptom of a range of diverse medical conditions not primarily to do with the skin. So, although it’s an ‘essential’ symptom when diagnosing eczema, it’s not a symptom that is specific to eczema alone.’
While itching is an ‘essential’ symptom when diagnosing eczema, it’s not specific to eczema alone.
We still do not fully understand what causes itching, but nerve fibres that transmit the itch sensation appear to exist within the skin. ‘Like other nerves, they are ultimately connected to the spinal cord and so to the brain,’ says Dr Henderson. ‘It used to be thought that the sensation of pain travelled along the same nerve fibres, but this now seems to be unlikely.’
Interestingly, the two sensations can act against each other. ‘Relief from severe itching may come from pain – as might be seen in someone who prefers the discomfort of a very hot bath to that of constant itching,’ he says. ‘The act of scratching may itself cause nerve signals to travel down the pain fibres, blocking the sensation of itch from being experienced.’
🔷 Skin discolouration
Discolouration of the skin usually means increased blood flow. ‘An extensive network of tiny blood vessels (capillaries) is present in the deeper layers of the skin that project loops of smaller vessels into the more superficial layers,’ says Dr Henderson. ‘The very top layer of skin is composed of dead skin cells and has no blood supply, so a superficial cut to this level will not bleed. When skin is inflamed, the blood vessels widen, increasing blood flow.’
The process of inflammation in eczema is complex and can be triggered for many reasons, but an important factor is the presence of bacterial infection. ‘When it gets into the deeper layers of the skin, there’s usually a marked increase in discolouration and heat from the tissues,’ Dr Henderson explains. ‘Recognising that this may be due to infection is important in bringing the eczema under control. In babies, it’s often the face that is affected.’
🔷 Skin thickening
Patches of skin that have been inflamed by eczema for a while are usually much thicker than unaffected skin. ‘This often occurs as a protective response to the repeated trauma of scratching or rubbing,’ Dr Henderson explains. ‘Eczema often affects the skin in areas around joints such as the elbow, behind the knees and in front of the ankles, where the skin needs to be flexible.’ You might notice splits in the skin, because it’s unable to bend as it would normally.
The microscopic study of skin structure in eczema shows there is less adhesion between the skin cells, particularly in the upper layers of the skin. ‘This contributes to scaling and makes it easier for skin bacteria to get into the deeper layers, between the gaps,’ Dr Henderson says. ‘It also makes it possible for tissue fluids to ooze between the cells and, if sufficient, to gather into collections or blisters.’ Small blisters may be seen in active eczema but occasionally large ones may occur – either due to the eczema or skin infection, when the blisters may be filled not only with clear fluid but also pus.
The fluid that oozes from inflamed skin is rich in protein, Dr Henderson explains. ‘When this dries out in contact with air, the protein is left behind as a crusty deposit,’ he says. ‘Often this occurs in conjunction with infection, when the infected crusts typically have a golden colour. ’
Grades of eczema
Eczema is classified according to how severe and for how long it has been active:
🔶 Acute eczema
‘Acute’ means of rapid onset. Often conditions that come on over a short period of time are also quite vigorous in their activity, although strictly speaking ‘acute’ should not be taken to be another word for ‘severe’. Acute eczema would therefore be an area that recently flared up, would probably have blisters and possibly oozing or crusts.
🔶 Chronic eczema
‘Chronic’ properly means long-standing. Once the initial phase of activity has died down, the skin becomes dry, scaly, thickened and cracked.
🔶 Infected eczema
Infection can occur at any stage of eczema. It won’t always be obviously different from acute eczema, unless there are pus-filled blisters.
While there’s no specific cure for eczema, there are things you can do to manage the condition and avoid flare-ups. ‘Eczema treatment is generally effective in most people – although severe eczema can be difficult to get rid of – and consists of three key areas: irritant avoidance, moisturising the skin and using steroid creams if required,’ Dr Henderson says.
‘It’s unusual to be able to identify and eliminate a single agent causing the skin reaction, and many people with eczema have to settle with improving their condition rather than getting rid of it altogether,’ he adds. Read on for the most common eczema treatment options:
Dry skin is a key trigger for atopic eczema, so keeping it well-moisturised is essential. Emollients is the general term given to moisturising creams, lotions, ointments and additives for the bath or shower that keep the skin supple and moist – and so reduce the chance of an eczema flare. Using an emollient regularly several times a day is vital.
- Use them liberally every day, even when the skin appears normal. You cannot overuse them.
- Ointments often last longer than creams and can be more moisturising but can be greasy and messier to use.
- Rub them into the skin in the direction of hair growth rather than against it.
- Consider using pump dispensers rather than pots of ointments or creams to help prevent infection.
- Add an emollient to the bath or an emollient shower gel to help prevent the skin from drying out as baths and showers dry the skin.
✔️ Steroid creams and ointments
If simple moisturisers don’t stop flare-ups, a topical steroid (cream or ointment) may be required. ‘They work by reducing skin inflammation and vary in strength, with the strongest ones having the greatest effects – but also the biggest risk of side effects if used long-term,’ says Dr Henderson. ‘Generally, steroid creams should be used if the skin is moist, and ointments if it’s dry. One to two weeks of topical steroid treatment is usually enough to treat an eczema flare up, although a longer course is sometimes needed.’ They’re usually applied once or twice a day on the affected area of skin – unlike emollients, which are applied all over the body.
One to two weeks of topical steroid treatment is usually enough to treat an eczema flare up, although a longer course is sometimes needed.
It’s important not to apply too much steroid to the skin, he adds. ‘It should be applied in a fingertip unit – the amount of cream or ointment that fits on a fingertip from the end of the finger to the first finger crease,’ says Dr Henderson. ‘One fingertip unit is enough to treat a skin area twice the size of the flat of your hand with the fingers together. After putting a topical steroid onto the skin always wash your hands – unless it’s your hands that need treating – and use emollients as usual too.’ Use your emollient first, wait 10 minutes, then apply steroid onto moist skin.
Occasionally eczema can become infected and a course of antibiotics may be required. If this occurs, dispose of the creams and ointments you have and obtain a fresh supply. ‘This reduces the risk of contaminated creams continuing to infect the skin,’ says Dr Henderson.
Although irritant avoidance, emollients and topical steroids are usually all that are required to treat eczema, there can be occasions when further treatment is required – sometimes under the care of a dermatologist. Examples of such treatments include tar shampoos, steroid tablets, skin soaks and topical immunomodulators.
What helps eczema flare-ups?
Flare-ups often occur for no obvious reason. To help reduce itching and soothe inflamed skin, follow these basic tips to reduce skin irritation:
✔️ Avoid scratching the skin whenever possible.
✔️ Keep nails short and rub the skin – rather than scratch – if you have to.
✔️ Avoid biological detergents and always rinse clothes well after washing them.
✔️ Avoid fluctuations in skin temperature.
✔️ Avoid perfumed soaps and bubble baths, which dry out the skin.
✔️ Gently pat the kin dry with a soft towel after showering or bathing.
✔️ Avoid harsh fabrics on the skin, such as wool.