What is the treatment for nummular dermatitis?

Treatment of Nummular Dermatitis

High or ultra-high potency topical corticosteroids applied twice daily are the mainstay of therapy for nummular dermatitis, combined with aggressive emollient use and identification of potential triggers. 1

First-Line Topical Corticosteroid Therapy

• Initiate treatment with high-potency topical corticosteroids (e.g., triamcinolone acetonide 0.1% or clobetasol propionate 0.05%) applied twice daily to affected coin-shaped plaques for 2-4 weeks. 2, 3, 1

• Ultra-high potency corticosteroids like clobetasol propionate 0.05% achieve clear/almost clear status in 67.2% of patients within 2 weeks and should be used for severe or recalcitrant lesions. 2

• Apply topical corticosteroids to clean, slightly damp skin for optimal absorption. 2

• For recalcitrant lesions, occlusive dressings may be used to enhance penetration, though this should be discontinued if secondary infection develops. 3

• The typical duration of active treatment is 2-4 weeks, after which transition to maintenance therapy is critical to prevent relapse. 2

Essential Adjunctive Emollient Therapy

• Liberal application of emollients is non-negotiable and must be used at least twice daily throughout treatment, not as an optional add-on. 2, 1

• Apply alcohol-free moisturizers containing 5-10% urea or glycerin-based formulations to restore the compromised skin barrier that characterizes nummular dermatitis. 2

• Apply corticosteroids first, wait 15-30 minutes, then apply emollients to avoid diluting the steroid. 2

• Oil-in-water creams or ointments are preferred over alcohol-containing lotions which can exacerbate dryness. 2

• Two-thirds of nummular dermatitis patients have co-existing xerosis (dry skin), making aggressive moisturization essential for treatment success. 4

Maintenance Therapy to Prevent Relapse

• After achieving initial control (typically 2-4 weeks), transition to proactive maintenance therapy with medium-potency topical corticosteroids applied twice weekly (weekend therapy) to previously affected areas for 16-20 weeks. 2

• This twice-weekly maintenance approach reduces relapse risk by 3.5-fold compared to stopping steroids entirely, with 87.1% remaining flare-free versus 65.8% with emollient alone. 2

• Continue daily emollient use indefinitely during the maintenance phase. 2

• The twice-weekly maintenance regimen shows only 1% incidence of skin thinning in trials up to 52 weeks, making it safe for prolonged use. 2

Trigger Identification and Avoidance

• Screen for and address potential aggravating factors, as nummular dermatitis has a chronic, relapsing course strongly influenced by triggers. 4, 1

• Emotional stress and alcohol consumption are significant aggravating factors that should be addressed. 4

• Avoid hot water baths, harsh soaps, and irritating skin care products that worsen xerosis. 1

• Consider patch testing in chronic, recalcitrant cases, as contact allergy (particularly to nickel) is common in nummular dermatitis patients. 4, 1

• Perform panoramic dental X-ray screening in treatment-resistant cases, as latent odontogenic infections may be an overlooked aggravating factor. 5

  • In one case series, 11 of 13 patients with severe, treatment-resistant nummular eczema improved after dental infection treatment. 5

Treatment Algorithm Based on Severity

For mild disease (few lesions, minimal pruritus):

• Start with regular emollients twice daily minimum and gentle cleansing. 2
• Add medium-potency topical corticosteroids if no improvement after 2 weeks. 2

For moderate disease (multiple lesions, significant pruritus):

• Initiate high-potency topical corticosteroids twice daily immediately. 2, 1
• Apply liberal emollients throughout the day. 2

For severe disease (extensive lesions, intense pruritus affecting quality of life):

• Use ultra-high potency topical corticosteroids (clobetasol 0.05%) for 2-4 weeks maximum. 2
• Consider wet wrap therapy for severe flares. 2
• Evaluate for underlying triggers including dental infections. 5

Critical Pitfalls to Avoid

• Undertreatment with low-potency steroids is a common error—nummular dermatitis requires high or ultra-high potency corticosteroids, not mild hydrocortisone preparations. 1

• Failure to implement maintenance therapy leads to rapid relapse—do not stop corticosteroids abruptly after clearing; transition to twice-weekly application. 2

• Neglecting emollients significantly compromises outcomes—these are essential components of treatment, not optional adjuncts. 2, 1

• Nummular dermatitis has a chronic course with mean disease duration often extending months to years, so set realistic expectations with patients. 4

• The condition significantly impairs quality of life (mean DLQI score 9.2), with itching causing the most impairment, particularly in younger patients and those with trunk or extensive lesions. 4

When to Escalate Beyond Topical Therapy

• Consider advanced therapies only after failure of optimized topical therapy including appropriate-potency corticosteroids, adequate duration (minimum 4 weeks), and consistent emollient use. 2

• For refractory nummular-type atopic dermatitis in adults, dupilumab shows significant efficacy with reduction in EASI, pruritus VAS, and DLQI scores after 16 weeks of treatment. 6

• Phototherapy (narrowband UVB) should be considered before systemic immunomodulatory agents in cases unresponsive to topical management. 2

• Topical calcineurin inhibitors (tacrolimus 0.03-0.1% or pimecrolimus 1%) can be used as steroid-sparing alternatives for maintenance therapy, though evidence is extrapolated from atopic dermatitis studies. 7