What is the recommended management for seborrheic dermatitis in adults, including first‑line topical antifungal therapy, adjunctive corticosteroids or calcineurin inhibitors, supportive measures, and second‑line options?

Management of Seborrheic Dermatitis in Adults

First-line treatment for seborrheic dermatitis combines topical antifungal agents (ketoconazole 2% cream or shampoo) with low-potency topical corticosteroids (hydrocortisone 1%) for 2-4 weeks maximum, supported by gentle cleansing and fragrance-free moisturizers. 1

First-Line Topical Antifungal Therapy

Ketoconazole 2% is the gold standard first-line antifungal agent, demonstrating an 88% response rate after initial treatment. 1 For scalp involvement, use ketoconazole 2% shampoo applied twice weekly, as shampoos, gels, solutions, or foams are superior to creams and ointments in hair-bearing areas. 1 Alternative antifungal options include ciclopirox olamine, selenium sulfide 1%, and clotrimazole, all of which have demonstrated efficacy in controlled trials. 1, 2, 3

Apply antifungal therapy once to twice daily to affected areas, continuing for at least 2-4 weeks even after visible improvement. 1 After initial clearance, transition to maintenance therapy with ketoconazole shampoo 1-2 times weekly to prevent recurrence. 1

Adjunctive Anti-Inflammatory Therapy

For significant erythema and inflammation, add hydrocortisone 1% cream or prednicarbate 0.02% cream to affected areas. 1 These low-potency corticosteroids reduce inflammation while minimizing adverse effects. 1

Critical safety consideration: Never use medium- or high-potency corticosteroids (triamcinolone, mometasone, clobetasol) on facial skin, as they carry unacceptable risks of skin atrophy, telangiectasia, and tachyphylaxis. 1 Limit all corticosteroid use on the face to a maximum of 2-4 weeks. 1

For patients requiring prolonged anti-inflammatory therapy beyond 4 weeks or when corticosteroids are contraindicated, topical calcineurin inhibitors (tacrolimus or pimecrolimus) are the preferred alternative for facial involvement. 1, 3 Pimecrolimus has been extensively studied for facial seborrheic dermatitis with strong evidence supporting its efficacy and safety profile. 3

Essential Supportive Measures

Avoid all alcohol-containing preparations on the face, as they markedly worsen dryness and precipitate disease flares. 1 This is a critical pitfall that frequently undermines treatment success.

Use mild, pH-neutral (pH 5) non-soap cleansers or dispersible creams as soap substitutes to preserve the skin's natural lipid barrier. 1 Apply fragrance-free moisturizers containing urea (≈10%) or glycerin immediately after bathing to damp skin to create a surface lipid film that prevents transepidermal water loss. 1 Reapply moisturizer every 3-4 hours and after each face washing. 1

Avoid products containing neomycin, bacitracin, or fragrances, as these have high sensitization rates (13-30% with neomycin). 1 Also avoid perfumes, deodorants, harsh soaps, and greasy or occlusive products that can promote folliculitis. 1

Use tepid (not hot) water for cleansing, and pat skin dry with clean towels rather than rubbing. 1

Second-Line and Adjunctive Options

For scalp involvement with thick scaling, coal tar preparations (1% strength preferred) can reduce inflammation and scaling when applied not more than twice daily. 1 Alternatively, salicylic acid 0.5-2% lotion can be applied once daily, gradually increasing to twice or three times daily if tolerated. 1 However, avoid salicylic acid 6% preparations in children under 2 years, and monitor children under 12 years for salicylate toxicity with prolonged use. 1

For moderate to severe pruritus, oral antihistamines (cetirizine, loratadine, fexofenadina) can provide symptomatic relief, though topical antihistamines offer no benefit. 1 Topical polidocanol-containing lotions may provide additional relief for pruritus. 1

For patients with significant inflammation and itching who respond inadequately to ketoconazole alone, adding clobetasol propionate 0.05% shampoo twice weekly to the scalp (not face) provides superior efficacy with sustained effect during maintenance. 1

Severe or Refractory Cases

Refer to dermatology if symptoms persist despite 4-6 weeks of appropriate first-line therapy, if there is diagnostic uncertainty, recurrent severe flares despite optimal maintenance, or need for second-line treatments. 1

For recalcitrant cases not responding to topical therapy, narrowband UVB phototherapy has demonstrated efficacy in open studies and can be considered. 1 Avoid applying moisturizers or topical products immediately before phototherapy, as they create a bolus effect. 1

Systemic antifungal agents (terbinafine, itraconazole) may be considered for severe and/or resistant cases. 2, 4

Emerging options include topical phosphodiesterase-4 inhibitors (roflumilast 0.3% foam), which show promise as noncorticosteroid alternatives. 4

Monitoring for Complications

Watch for secondary bacterial infection (increased crusting, weeping, pustules) suggesting Staphylococcus aureus, which requires oral flucloxacillin. 1 Also monitor for herpes simplex superinfection, characterized by grouped vesicles or punched-out erosions, requiring immediate oral acyclovir. 1

Common Pitfalls to Avoid

Undertreatment due to fear of corticosteroid side effects is common—use appropriate potency for adequate duration, then taper. 1 Conversely, avoid overuse of non-sedating antihistamines, which provide no benefit in seborrheic dermatitis. 1

Do not confuse persistent mild itching after treatment with treatment failure, as mild burning or itching from inflammation can persist for days after yeast is eliminated and does not indicate need for re-treatment. 1

Ensure proper differentiation from psoriasis (well-demarcated indurated plaques with thick silvery scale), atopic dermatitis (more intense pruritus with lichenification), contact dermatitis (sharp demarcation corresponding to contact area), and other conditions that require different treatment approaches. 1