What is the diagnosis for an adult or adolescent patient presenting with dandruff and flakes on scales like dried scales, who has been prescribed ketoconazole (antifungal medication)?

Seborrheic Dermatitis with Dandruff and Scalp Scaling

The condition you're describing—dandruff with flakes and dried scales on the scalp—is seborrheic dermatitis, and your prescription of ketoconazole is appropriate and evidence-based. 1, 2, 3

Diagnosis and Pathophysiology

• Seborrheic dermatitis (or its milder form, simple dandruff) presents with flaking, scaling, and often pruritus of the scalp, affecting up to 50% of the population at some point in their lives 2
• The causative agent is the lipophilic yeast Malassezia species (previously called Pityrosporum ovale), which proliferates in the scaly epidermis of affected patients 2, 3
• The condition is most prevalent in young men and can be aggravated by humidity changes, trauma from scratching, seasonal variations, and emotional stress 2

Treatment Recommendations

Ketoconazole Formulation Selection

• Ketoconazole 2% shampoo is superior to 1% formulation for moderate to severe seborrheic dermatitis and should be your first choice 4
• The 2% formulation demonstrates significantly greater reduction in flakiness and Malassezia density compared to 1% (p < 0.001) after 2-4 weeks of treatment 4
• Ketoconazole 2% shampoo produces an excellent response in 88% of patients with moderate to severe seborrheic dermatitis when used twice weekly for 2-4 weeks 3

Treatment Protocol

Acute Phase (2-4 weeks):

• Apply ketoconazole 2% shampoo twice weekly to the affected scalp 3
• Allow the shampoo to remain on the scalp with adequate lathering time before rinsing 2
• Clinical improvement typically occurs within the first 2-4 weeks 3

Maintenance Phase (after initial clearance):

• Continue ketoconazole 2% shampoo once weekly for prophylaxis to prevent relapse 3
• This maintenance regimen reduces relapse rates from 47% (placebo) to 19% (active weekly treatment) over 6 months 3

Alternative and Adjunctive Options

• If ketoconazole is unavailable or ineffective, alternative antifungal shampoos include selenium sulfide, ciclopirox olamine 1.5%, or zinc pyrithione 2, 5
• Ciclopirox olamine 1.5% shampoo demonstrates comparable efficacy to ketoconazole 2% for mild to moderate dandruff 5
• For thick, adherent scalp plaques, overnight occlusion with salicylic acid or urea oil can help soften scales before shampooing 2

Important Clinical Pitfalls

• Do NOT use ketoconazole cream for scalp seborrheic dermatitis—the shampoo formulation is specifically designed for scalp application and is far more effective 6, 3
• Ketoconazole cream is indicated for cutaneous candidiasis and tinea infections of non-scalp skin, not for scalp conditions 6
• Advise patients to discontinue hair sprays and pomades during treatment, as these can aggravate the condition 2
• The topical shampoo formulation has minimal systemic absorption and is safe for prolonged use, unlike oral ketoconazole which carries hepatotoxicity risk 1

When to Reassess

• If no clinical improvement occurs after 4 weeks of appropriate twice-weekly treatment, reconsider the diagnosis 6
• Persistent symptoms may indicate a different condition such as psoriasis, atopic dermatitis, or tinea capitis requiring alternative management 1