Eczema is one of the most common chronic skin conditions, affecting up to 20% of children and 3% of adults worldwide. The persistent itch and irritation can significantly impact sleep, quality of life and daily well-being.
In this article we explain exactly what eczema is, what causes it, what it looks like, and what you can do about it.
What is eczema?
Atopic dermatitis — commonly known as eczema — is a chronic, inflammatory skin condition that makes the skin red, itchy and sometimes swollen. "Atopic" refers to a hereditary tendency towards allergic reactions, and the condition is closely linked to asthma and hay fever in what is called the atopic triad.
Eczema is an umbrella term for several inflammatory skin conditions. Atopic dermatitis is the most common form, but an itchy rash can also be caused by contact dermatitis, triggered by something the skin has touched, or seborrhoeic dermatitis, which affects greasy areas such as the scalp, eyebrows and sides of the nose.
Eczema is not contagious. You cannot spread it to others or catch it from another person. It is an internal condition driven by the immune system and genetics.
What does eczema look like?
Eczema can look very different depending on a person's age and skin type:
- Dry, scaly patches: Typically on the neck, face and around the eyes in adults. The skin may look rough and dull.
- Redness and swelling: Inflamed areas look red and may feel warm. In darker skin tones, redness may appear as a darker discolouration.
- Intense itching: Itching is often the most troublesome symptom and can worsen at night. Scratching provides temporary relief but worsens the skin and can lead to infection.
- Raw, cracked or bleeding skin: Repeated scratching can lead to open sores and cracks in the skin, increasing the risk of bacterial infections.
- Lichenification: With long-term itching and scratching, the skin can become thicker and leathery — a sign of chronic eczema.
In adults, eczema most commonly affects the insides of the elbows and the backs of the knees, along with the wrists, neck and face. In infants and young children, it often appears on the face and torso.
Distribution is an important clue: atopic eczema sits in the skin creases, whereas scaly plaques on the outer points of the elbows and knees more often point to psoriasis.
When to seek urgent help
Seek same-day medical care if eczema suddenly worsens with clusters of small, painful, punched-out sores or blisters, especially with fever or feeling unwell. This can be eczema herpeticum — a herpes infection of eczematous skin that needs urgent antiviral treatment.
Why does eczema happen?
The exact cause of eczema is not fully understood, but research points to a combination of factors:
What happens to the skin barrier?
It becomes leaky. In people with eczema, the skin barrier is impaired, making it easier for irritants and allergens to penetrate and for moisture to evaporate out. A mutation in the gene for filaggrin — a protein essential for a healthy skin barrier — is a common cause.
Why does the immune system overreact?
Because it is tuned towards an allergic type of inflammation. The immune system overreacts to seemingly harmless substances such as house dust mites, pet dander or certain foods, triggering an inflammatory response in the skin. This is a similar mechanism to other atopic conditions such as asthma and allergies.
Is eczema hereditary?
To a large extent. Eczema runs in families. If one or both parents have eczema, asthma or hay fever, the risk of the child developing atopic dermatitis is significantly increased.
What triggers a flare?
Even with a genetic predisposition, eczema usually requires a trigger to flare up. Common triggers include:
- Stress and psychological strain
- Weather changes — especially cold, dry weather
- Harsh soaps, fragrances and cleaning products
- Certain foods, in a minority of patients — most often cow’s milk, egg, peanut or wheat in young children with proven allergy. Never eliminate foods without allergy testing and medical advice; unnecessary elimination can cause nutritional deficiency and may increase the risk of true food allergy.
- Synthetic fabrics and wool
- Sweat and overheating
Who gets eczema?
Anyone can develop eczema, but it is most common in:
- Infants and children: Up to 20% of all children have atopic dermatitis. The condition often develops in the first year of life and improves for many during childhood or teenage years.
- Adults with family history: Around 3% of adults live with chronic eczema, and many find the condition returns even if it improved in childhood.
- People with an atopic background: If you or your family have allergies, asthma or hay fever, the risk of eczema is higher.
What can you do about eczema?
Eczema cannot be cured, but it can be effectively controlled with the right treatment and skincare routine:
Moisturiser (most important daily treatment)
Apply a rich, fragrance-free moisturiser or emollient at least twice daily — even between flares. This strengthens the skin barrier and reduces the frequency and severity of flares.
Topical corticosteroids
Corticosteroid creams (cortisone) suppress inflammation and itching during flares. They come in varying strengths — from mild to very potent. In Denmark, mild hydrocortisone 1% is available over the counter at the pharmacy, while stronger steroids require a prescription from your GP or a dermatologist.
Immunomodulators (calcineurin inhibitors)
Creams such as tacrolimus and pimecrolimus are a steroid-free alternative for sensitive areas like the face, around the eyes and the neck. They avoid the skin thinning that long-term steroid use can cause, but they commonly sting or burn for the first few days, and treated areas need good sun protection.
Systemic treatment (severe eczema)
For severe or widespread eczema, a dermatologist may prescribe biological treatment such as dupilumab, tralokinumab or lebrikizumab, oral JAK inhibitors such as upadacitinib or abrocitinib, older oral immunosuppressants, or narrowband UVB phototherapy.
Avoid triggers
Identify and avoid your personal triggers. Use fragrance-free products and soft clothing, and take short, lukewarm showers rather than long hot baths.
Medical classification: Atopic eczema is classified as EA80 in the WHO's International Classification of Diseases (ICD-11). It is characterised as a chronic, inflammatory condition with itchy, red and dry skin. Treatment includes moisturisers, topical steroids and immunomodulators.
Frequently asked questions
Can eczema disappear completely?
Many children grow out of eczema during their teenage years, but for others it remains a chronic condition requiring ongoing management. With the right treatment, however, eczema can be brought under good, long-term control.
Is eczema the same as dry skin?
No. Dry skin can occur in anyone and is caused by a lack of moisture. Eczema, however, is an inflammatory condition with an immunological basis that requires medical treatment beyond simply moisturising.
When should I contact a dermatologist?
Contact a dermatologist if itching is disturbing your sleep, the skin starts to weep or become infected, over-the-counter remedies are not helping, or if eczema is significantly affecting your daily life. If eczema suddenly worsens with small, painful blisters and fever, seek medical care the same day.
Get an assessment within 48 hours
Upload photos of your skin via the SKIND app and receive a personal assessment and treatment plan from a certified dermatologist — no hospital waiting list.
Disclaimer: This article is for informational purposes only and does not replace professional medical advice. Always consult a doctor or dermatologist for personal guidance and assessment of skin changes.