Eczema is a chronic skin condition that causes dry, itchy, inflamed patches on the skin. It affects an estimated 129 million people worldwide, making it one of the most common skin disorders. The term “eczema” is often used interchangeably with “atopic dermatitis,” which is its most common form. It tends to come and go in flare-ups, and while it often starts in childhood, it can develop or persist at any age.
What Happens in the Skin
Healthy skin acts as a tight barrier, locking in moisture and keeping out irritants, allergens, and bacteria. In eczema, that barrier is compromised. A key player is a protein called filaggrin, which helps skin cells form a strong, flat surface layer. When the body doesn’t produce enough filaggrin, the skin loses moisture more easily and becomes more vulnerable to outside substances that trigger inflammation.
The immune system compounds the problem. In people with eczema, certain immune cells overreact, producing inflammatory signals that further weaken the skin barrier and reduce filaggrin levels even more. This creates a cycle: a weakened barrier lets irritants in, the immune system overreacts, and that reaction damages the barrier further. The immune response also suppresses the skin’s natural antimicrobial defenses, which is why people with eczema are prone to skin infections.
Genetics and Who Gets It
Eczema has a strong genetic component. Around 40 different mutations in the filaggrin gene have been identified in people with the condition. Between 20 and 30 percent of people with eczema carry one of these mutations, compared with 8 to 10 percent of the general population. Having mutations in both copies of the gene raises the risk further and typically leads to more severe disease.
But genes alone don’t determine who develops eczema. A family history of eczema, asthma, or hay fever increases your likelihood, and environmental factors play a major role in whether the condition actually develops or stays quiet.
Common Triggers for Flare-Ups
Eczema flares rarely happen randomly. Most people learn to identify specific triggers over time, though they vary from person to person. The most well-established include:
- Irritants: soaps, detergents, fragrances, wool clothing, and harsh cleaning products
- Allergens: dust mites, pet dander, pollen (especially ragweed), and mold
- Stress: emotional stress from work, relationships, or family conflict is one of the most commonly reported triggers
- Air pollution: children growing up near busy roads have a higher risk of developing eczema, and exposure to volatile organic compounds from new furniture, paint, or building materials can provoke flares
- Tobacco smoke: one of the most significant indoor allergens for eczema
- Climate and weather: low humidity, cold air, and sudden temperature changes can dry the skin and trigger symptoms
About 80 percent of adults with eczema show immune sensitivity to airborne or food allergens. For eczema concentrated on the head and neck, pollen exposure during allergy season is a particularly common culprit.
What Eczema Looks and Feels Like
Itching is the hallmark symptom. It can range from mild and annoying to intense enough to disrupt sleep. The itch often comes before visible changes in the skin, and scratching makes things worse by further damaging the barrier.
On lighter skin, eczema typically appears as red or dark pink patches that are dry, scaly, and sometimes oozing or blistered during severe flares. On darker skin, the picture is different. Inflammation shows up as patches of darker pigmentation rather than obvious redness, which means eczema severity is often underestimated in people with darker skin tones. Follicular prominence, where the eczema appears as small itchy bumps rather than flat patches, is also more common on darker skin. Dry skin and scale tend to be more visible because they appear white or grey against the skin.
In infants and young children, eczema commonly affects the face, scalp, and outer surfaces of the arms and legs. In older children and adults, it typically settles into the creases of the elbows, behind the knees, and around the neck and wrists. Chronic scratching causes the skin to thicken and develop a leathery texture, a change called lichenification. After a flare resolves, areas of lighter or darker discoloration can linger for months, particularly in people with darker skin.
How Eczema Is Diagnosed
There’s no blood test or biopsy that confirms eczema. Diagnosis is based on a pattern of features: persistent itching, a chronic or relapsing course, and the characteristic distribution of rashes for the person’s age. A personal or family history of asthma or hay fever supports the diagnosis. Doctors also look for consistently dry skin and rule out other conditions that can look similar, such as contact dermatitis, psoriasis, or fungal infections.
Daily Skin Care and Moisture
Consistent moisturizing is the foundation of eczema management, not an optional add-on. Clinical guidelines recommend using emollients generously, in the range of 250 to 500 grams per week, which is roughly one to two standard tubs. The best time to apply is right after bathing, while the skin is still slightly damp. This “soak and seal” approach helps trap water in the outer skin layer.
Beyond moisturizing, avoiding known irritants matters. Fragrance-free soaps and detergents, soft cotton clothing, and keeping indoor humidity at a comfortable level all help reduce the frequency of flares. A diverse diet during the first years of life also appears to protect against allergic conditions, including eczema, in children who are genetically at risk.
Treatment Options
When moisturizing alone isn’t enough, prescription treatments help control inflammation and itching. The approach generally follows a stepwise pattern based on severity.
Topical Steroids
These have been the standard treatment for over 50 years. They come in a range of strengths, from mild over-the-counter options to potent prescription formulas. A common strategy is to use a stronger treatment daily for two to three weeks to get a flare under control, then switch to applying it just two days per week to maintain clear skin. This “get control, keep control” approach has strong evidence behind it and helps minimize side effects from prolonged daily use.
Calcineurin Inhibitors
These are non-steroid creams that calm the immune response in the skin. They’re particularly useful for sensitive areas like the face and eyelids where long-term steroid use is less desirable. Applied twice daily during flares, they reduce itching and severity relatively quickly and can also be used in a maintenance schedule similar to topical steroids.
Biologics and Oral Medications
For moderate to severe eczema that doesn’t respond to topical treatments, newer systemic options are available. Injectable biologics that target specific immune pathways are now approved for patients ranging from infants as young as 6 months through adulthood. Oral medications that block certain inflammatory enzymes were approved in 2022 for adolescents and adults whose eczema hasn’t responded to other systemic treatments. These therapies represent a significant shift for people with severe disease who previously had limited options.
Infection Risks
Broken, inflamed skin is an open invitation for bacteria, particularly Staphylococcus aureus. The altered pH and reduced antimicrobial defenses in eczema-prone skin create ideal conditions for this bacterium to thrive. Once established, S. aureus produces toxins that further break down the skin barrier and ramp up inflammation, worsening the eczema itself. People with filaggrin gene mutations face a seven-times higher risk of recurrent skin infections requiring antibiotics compared to those with eczema but normal filaggrin genes.
A rarer but more serious complication is eczema herpeticum, a widespread herpes virus infection of eczema-affected skin. It tends to occur alongside bacterial infections and is more common in people with filaggrin mutations. Rapidly spreading painful blisters, fever, or feeling unwell during an eczema flare can signal this complication, which requires prompt treatment.
Does Eczema Go Away?
The traditional teaching is that eczema develops in the first two years of life and clears up in most children by age 10 to 12. There’s truth to this, but the picture is more nuanced than it sounds. Studies that follow children into their teenage years and adulthood often find that eczema returns or persists more frequently than shorter studies suggest. People with filaggrin gene mutations are more likely to have severe, persistent disease that carries into adulthood. For some, eczema first appears in adulthood with no childhood history at all.
Even when eczema resolves, the underlying tendency toward a sensitive skin barrier often remains. Maintaining a good moisturizing routine and avoiding known triggers helps keep the skin stable long after active flares have stopped.