Management of Nummular Eczema

First-Line Topical Corticosteroid Strategy

The American Academy of Dermatology recommends applying moderate barging moderate-to-potent topical corticosteroids once or twice daily to the coin-shaped lesions, as nummular eczema lesions are often thick and lichenified, requiring higher potency preparations than mild eczema 1, 2
Use the least potent preparation that controls the disease, and implement "steroid holidays" (short breaks) when possible to minimize side effects 1
Very potent and potent corticosteroids should be used with caution for limited periods only 1

Apply emollients liberally and frequently throughout the day, immediately after bathing, as this provides a surface lipid film that retards water loss - this is critical since two-thirds of nummular eczema patients have co-existing skin dryness 1, 2
Continue aggressive emollient use even when lesions appear controlled, as this is the cornerstone of maintenance therapy 1, 2
Use soap-free cleansers exclusively and avoid hot water, as soaps and detergents remove natural skin lipids and worsen the underlying dry skin 1, 2

Consider ichthammol 1% in zinc ointment or coal tar solution 1% for thick, lichenified nummular plaques, as these can be particularly useful for healing chronic lesions 3, 4
Ichthammol paste bandages can be especially effective for lichenified eczema typical of nummular lesions 3, 4

Prescribe sedating antihistamines (such as diphenhydramine or hydroxyzine) exclusively at nighttime for severe itching, as their benefit comes from sedation rather than direct anti-pruritic effects 1, 2
Non-sedating antihistamines have no value in eczema and should not be used 1, 2

Watch for increased crusting, weeping, or pustules, which indicate secondary bacterial infection with Staphylococcus aureus - this is common in nummular eczema 1, 2
Add oral flucloxacillin as first-line antibiotic while continuing topical corticosteroids 1, 2
Do not delay or withhold topical corticosteroids when infection is present - they remain the primary treatment when appropriate systemic antibiotics are given concurrently 1

After achieving clearance, apply topical corticosteroids twice weekly (weekend therapy) to previously affected sites to prevent relapse, as nummular eczema has a chronic and relapsing course 1

For treatment-resistant cases, consider narrow band ultraviolet B (312 nm) phototherapy 1

Systemic corticosteroids have a limited but definite role only for tiding occasional patients through acute severe flares after exhausting all other options - they should never be used for maintenance treatment 1

Failure to respond to moderate-to-potent topical corticosteroids after 4 weeks 1, 2
Need for systemic therapy or phototherapy 1, 2
Suspected eczema herpeticum (medical emergency) 1

The American Academy of Dermatology recommends using ointments or thick creams rather than lotions for nummular eczema, as the thick, lichenified plaques characteristic of this condition require maximum occlusion and penetration, with a strength of evidence based on multiple studies 5, 6
Fragrance-free formulations are essential to avoid irritation and sensitization in patients with nummular eczema, according to the National Eczema Association, with a high strength of evidence 5, 6
Urea-containing emollients (10-20%) are particularly effective for the hyperkeratotic, scaly plaques typical of nummular eczema, though urea concentrations ≥10% should be avoided in children under 1 year except on limited areas like palms and soles, as recommended by the British Association of Dermatologists 7

The National Eczema Society recommends applying emollients at least twice daily, with more frequent application (up to 3-4 times daily) for moderate-to-severe cases, with a moderate strength of evidence 5, 6
Emollients should be applied immediately after bathing (within 3 minutes of patting skin dry) to trap moisture when skin is most hydrated, according to the American Academy of Dermatology, with a high strength of evidence 5, 6
For adults, expect to use 200-400 grams per week when applying twice daily to affected areas, as estimated by the European Academy of Dermatology and Venereology 8

The American Academy of Dermatology recommends using lukewarm water only and limiting bathing to 10-15 minutes to prevent excessive drying, with a moderate strength of evidence 5, 6

The British Association of Dermatologists recommends avoiding urea concentrations ≥10% except for once-daily application to limited areas like palms and soles in infants and young children under 1 year 7
Urea-containing products (10-20%) can be used more liberally after age 2 years, according to the European Academy of Dermatology and Venereology 7

The National Eczema Society recommends continuing emollients throughout corticosteroid treatment, as they have documented steroid-sparing effects, with a high strength of evidence 5, 6