What Is Eczema? Types, Causes, Triggers and Natural Treatment (2026)

By Ava Huang, Herbal Science Researcher at QICAOGANGMU | Reviewed: March 2026 | Reading time: 10 minutes

Eczema affects over 230 million people worldwide - making it one of the most common chronic skin conditions on the planet. Yet despite how prevalent it is, eczema is frequently misunderstood, misdiagnosed, and poorly managed. Many people spend years treating it with products that do not address the underlying cause.

This guide covers what eczema actually is, all the different types including nummular and dyshidrotic eczema, what triggers flares, how Traditional Chinese Medicine classifies the condition, and the most effective natural treatment options with the evidence behind them.

What is eczema and what causes it?

Eczema is a chronic inflammatory skin condition characterised by dry, intensely itchy, red, and inflamed skin that follows a pattern of flares and remissions. The underlying cause involves two interacting factors: a defective skin barrier and immune dysregulation.

The skin barrier defect: In people with eczema, variants in the filaggrin gene result in a skin barrier that does not hold moisture effectively and does not block irritants and allergens from penetrating. The skin loses water too easily (high transepidermal water loss) and lets inflammatory triggers in too readily.

The immune component: The compromised barrier triggers a Th2-skewed immune response - the body over-produces cytokines including IL-4, IL-13, and TNF-alpha in response to triggers that would not affect normal skin. This creates the inflammatory cycle: barrier damage lets triggers in, which activates inflammation, which worsens the barrier, which lets more triggers in.

Eczema is not caused by poor hygiene and is not contagious. It runs in families alongside asthma and allergic rhinitis (hay fever) because all three share the same underlying Th2 immune predisposition - collectively called atopy.

The defining symptoms of eczema

• Intense itch - often worse at night and severe enough to disrupt sleep
• Dry, sensitive skin that feels tight or uncomfortable
• Red to brownish-grey patches
• Small raised bumps that may weep fluid when scratched
• Thickened, cracked, or scaly skin in chronic areas
• Swollen skin from repeated scratching

What are the different types of eczema?

Eczema is not a single condition - it is a group of related inflammatory skin conditions that share the feature of itchy, inflamed skin but differ in cause, location, and presentation.

Atopic dermatitis - the most common type

Atopic dermatitis is what most people mean by "eczema." It typically begins in childhood, often improves in adulthood, but can persist or recur throughout life. It affects the skin creases (inside elbows, behind knees, front of ankles), the wrists, hands, neck, and face - particularly around the eyes and mouth. It is driven by a Th2-skewed immune response and filaggrin barrier deficiency.

Nummular eczema (discoid eczema)

Nummular eczema produces clearly defined, coin-shaped (nummular = Latin for coin) circular patches of irritated skin, typically 2-10cm in diameter, on the arms, legs, and trunk. It is intensely itchy, may weep fluid, and then crusts over.

It is frequently mistaken for ringworm because of its circular shape - the difference is that ringworm has a ring shape with a clearer centre, while nummular eczema patches are uniformly inflamed throughout. Nummular eczema does not follow the crease-distribution of atopic dermatitis and is more common in middle-aged and older adults. Triggers include dry skin in winter, insect bites, and stress.

Dyshidrotic eczema (pompholyx)

Dyshidrotic eczema produces small, intensely itchy fluid-filled blisters on the palms, fingers, and soles of the feet. Blisters typically last 2-4 weeks before drying and peeling. Triggers include stress, heat, sweating, and contact with nickel or other metals. In Traditional Chinese Medicine, dyshidrotic eczema is a classic Damp-Heat pattern - the fluid in the blisters represents Dampness trapped beneath the skin surface combined with Heat.

Seborrheic dermatitis

Seborrheic dermatitis affects oily areas - the scalp, face (around the nose and eyebrows), and chest. It produces red, scaly, flaky patches and is associated with Malassezia yeast overgrowth. Dandruff is a mild form. In TCM, seborrheic dermatitis is classified as Damp-Heat in the Stomach and Spleen meridians, which map to the face and scalp. See the seborrheic dermatitis and pityrosporum folliculitis guide.

Contact dermatitis

Contact dermatitis is triggered by external substances rather than internal immune dysregulation. Irritant contact dermatitis (ICD) is caused by direct barrier damage from soaps, chemicals, and wet work. Allergic contact dermatitis (ACD) requires immune sensitisation to a specific allergen - the most common being nickel, fragrance, and rubber accelerants. See the contact dermatitis complete guide.

Stasis dermatitis

Stasis dermatitis affects the lower legs in people with poor venous circulation. Blood pooling in the lower legs causes skin inflammation, discolouration, and itching. More common in older adults. Treatment must address the underlying circulation alongside the skin.

What triggers eczema flares?

Eczema flares are triggered by the interaction of genetic predisposition with environmental factors. Identifying and avoiding your personal triggers is the single most effective management strategy - more effective than any cream alone.

• Dry skin - the most universal trigger. Cold, dry weather dramatically worsens eczema. The damaged barrier loses moisture faster in low humidity.
• Irritants - soaps, detergents, shampoos, bubble bath, disinfectants, and even juices from fresh fruit and vegetables damage the barrier directly.
• Environmental allergens - house dust mites, pet dander, pollen, and mould trigger the Th2 immune response. Dust mite reduction (encasing mattresses and pillows, washing bedding at 60 degrees) is consistently one of the highest-impact environmental interventions.
• Food allergens - dairy, eggs, nuts, wheat, and soy are the most common. Food allergens are more relevant in children under 5 than adults. A 2-4 week elimination diet identifies individual sensitivities.
• Stress - chronic stress maintains elevated inflammatory cytokines through glucocorticoid resistance. This is why eczema is often impossible to clear during a stressful period despite good topical treatment.
• Heat and sweating - heat activates itch nerve fibres and sweat is itself an irritant in eczema skin, containing inflammatory neuropeptides.
• Staphylococcus aureus - colonises eczema skin in over 90% of patients and significantly worsens inflammation through toxin release and barrier disruption. Stemonae Radix (Bai Bu) in QICAOGANGMU provides antimicrobial protection against Staph aureus.
• Wool and synthetic fabrics - cause mechanical irritation. Loose cotton is consistently better tolerated.
• Hormonal changes - many women find eczema worsens premenstrually, during pregnancy, or at menopause due to oestrogen effects on skin barrier function.

How does the gut-skin connection affect eczema?

People with eczema have measurably different gut microbiome compositions - lower Lactobacillus and Bifidobacterium and higher inflammatory bacteria. This gut dysbiosis drives systemic inflammation that manifests in the skin as itch, redness, and barrier dysfunction.

Probiotic supplementation (particularly Lactobacillus rhamnosus GG) has shown statistically significant reductions in eczema severity scores in multiple randomised controlled trials. Children born by Caesarean section have lower microbiome diversity and higher rates of atopic eczema - establishing the role of early gut colonisation in long-term skin health.

Practical dietary steps: reduce sugar, alcohol, and processed foods (which feed inflammatory gut bacteria). Increase fermented foods (yogurt, kefir, kimchi), omega-3 fats (oily fish, flaxseed), and anti-inflammatory vegetables. See the full dietary guide for itchy skin for the complete TCM food protocol.

How does Traditional Chinese Medicine understand and treat eczema?

TCM classifies eczema into patterns based on presentation rather than applying one diagnosis to all cases. This syndrome differentiation explains why two people with "eczema" may need completely different treatments.

The three core pathogenic factors in TCM eczema are Wind (moving, unpredictable itch that comes and goes), Dampness (weeping, oozing, vesicular presentations), and Heat (redness, inflammation, burning sensation). Most eczema presentations involve a combination:

• Wind-Heat - dry, intensely itchy, migratory eczema. Worse in warm weather. Often affects the face and upper body.
• Damp-Heat - weeping, red, oozing eczema. Affects skin folds, hands, and feet. Worse in humid conditions. Classic presentation of dyshidrotic eczema.
• Blood Deficiency/Wind-Dry - chronic, thickened, lichenified eczema. Dry rather than inflamed. More common in older patients and long-standing eczema.
• Spleen Deficiency with Damp - associated with digestive weakness. Often in children. Treated with Spleen-strengthening herbs alongside Damp-clearing ones.

This framework maps closely onto modern mechanisms: Wind corresponds to neurogenic itch signalling, Dampness to transepidermal water loss and microbial imbalance, and Heat to the Th2-driven inflammatory cytokine cascade.

See the full TCM guide to eczema and psoriasis for complete pattern descriptions and treatment principles.

What is the most effective natural treatment for eczema?

The most evidence-supported natural approach to eczema combines three elements: consistent emollient therapy, steroid-free herbal anti-inflammatory treatment, and trigger identification and avoidance.

Emollient therapy - the non-negotiable foundation

Moisturising is the single most important self-care measure for eczema - more important than any active topical treatment. Apply a fragrance-free, hypoallergenic emollient at minimum twice daily, within 3 minutes of bathing while skin is still slightly moist. For severe eczema, applying every 2-3 hours during waking hours significantly reduces flare frequency.

Herbal anti-inflammatory treatment - the evidence

QICAOGANGMU addresses eczema through the specific mechanisms that drive it:

• Sophora flavescens (Ku Shen) at 1.5% - matrine alkaloids inhibit Th2 immune response, reducing IL-4, IL-13, and TNF-alpha. Matched dexamethasone effects in eczema models. PMID: 36216196
• Cnidium monnieri (She Chuang Zi) at 3% - total coumarins improved atopic dermatitis and restored skin barrier in animal models. Osthole component desensitises TRPV1 itch receptors. PMID: 33634904
• Stemonae Radix (Bai Bu) at 0.5% - broad-spectrum antimicrobial protection against Staphylococcus aureus colonisation
• Borneolum Syntheticum at 2% - drives all active compounds past the compromised barrier into the viable epidermis. Independently reduces IL-6 and TNF-alpha. PMID: 31978868
• Menthol at 0.5% - immediate itch relief via TRPM8 cold receptor activation within minutes of application

A 2022 meta-analysis of 8 high-quality randomised placebo-controlled trials confirmed Chinese herbal medicine containing Sophora flavescens and Cnidium monnieri is effective and safe for atopic dermatitis. PMID: 36238577

When to use topical steroids

Topical steroids remain appropriate for acute, severely inflamed flares requiring rapid control. Use the minimum effective potency for the shortest necessary duration, then transition to herbal maintenance to reduce steroid frequency over time. See the complete guide to transitioning off steroid cream.

Frequently asked questions about eczema

What is eczema caused by?

Eczema is caused by the combination of filaggrin gene variants (which produce skin barrier defects) and Th2-skewed immune dysregulation. Environmental triggers - irritants, allergens, stress, heat, and infections - flare the condition in people with this underlying predisposition. Diet and gut microbiome composition also influence systemic inflammation levels and therefore eczema severity.

What is the difference between eczema and nummular eczema?

Nummular eczema is a specific subtype that produces coin-shaped circular patches rather than the diffuse patches of atopic dermatitis. It tends to affect middle-aged and older adults rather than children, does not follow the crease distribution of atopic eczema, and is more commonly triggered by dry skin and injury. Treatment principles are similar but nummular eczema requires particularly intensive moisturising as dry skin is its primary trigger.

Is eczema contagious?

No. Eczema is an immune and barrier condition - it cannot be passed from person to person. However, secondary bacterial infections that complicate eczema (Staphylococcus aureus, impetigo) can be contagious. If eczema skin looks infected - oozing pus, unusual smell, rapidly spreading redness or fever - seek medical advice promptly.

Can eczema be cured permanently?

There is no permanent cure for eczema. Many children outgrow it by adulthood. For adults, it can often be managed to the point of long periods of clear skin - the goal is remission with progressively less frequent and less severe flares rather than cure. Consistent treatment combining emollients, trigger avoidance, and anti-inflammatory therapy achieves this for most people.

What is the difference between eczema and psoriasis?

Eczema is driven by Th2 immune dysregulation and skin barrier defects (filaggrin variants). Psoriasis is driven by T-cell autoimmune attack causing abnormally rapid skin cell turnover (keratinocyte hyperproliferation). Eczema tends to affect skin creases and produce weeping, itchy rashes. Psoriasis produces thick, silvery-scaled plaques on elbows, knees, and scalp. Both conditions share NF-kB inflammatory pathways, which is why the same herbal ingredients (Sophora flavescens) are effective for both.

Why is eczema worse at night?

Eczema is worse at night for three reasons: the body's natural cortisol (anti-inflammatory) levels drop overnight; body temperature rises during sleep activating itch nerve fibres; and the lack of distraction makes itch perception more intense. The resulting sleep deprivation further worsens inflammation by elevating inflammatory cytokines. Menthol-based creams applied before bed provide cooling itch relief through the first part of the night.

What is the best natural treatment for eczema?

The most evidence-supported natural approach combines consistent emollient therapy (twice daily minimum, within 3 minutes of bathing) with herbal anti-inflammatory treatment containing Sophora flavescens and Cnidium monnieri, dietary adjustments reducing sugar, alcohol, and inflammatory foods, and systematic trigger identification and avoidance. QICAOGANGMU provides the herbal anti-inflammatory component - with documented NF-kB inhibition, Th2 suppression, and TRPV1 antipruritic action.